TY - JOUR A1 - Marenholz, Ingo A1 - Esparza-Gordillo, Jorge A1 - Rüschendorf, Franz A1 - Bauerfeind, Anja A1 - Strachan, David P. A1 - Spycher, Ben D. A1 - Baurecht, Hansjörg A1 - Magaritte-Jeannin, Patricia A1 - Sääf, Annika A1 - Kerkhof, Marjan A1 - Ege, Markus A1 - Baltic, Svetlana A1 - Matheson, Melanie C. A1 - Li, Jin A1 - Michel, Sven A1 - Ang, Wei Q. A1 - McArdle, Wendy A1 - Arnold, Andreas A1 - Homuth, Georg A1 - Demenais, Florence A1 - Bouzigon, Emmanuelle A1 - Söderhäll, Cilla A1 - Pershagen, Göran A1 - de Jongste, Johan C. A1 - Postma, Dirkje S. A1 - Braun-Fahrländer, Charlotte A1 - Horak, Elisabeth A1 - Ogorodova, Ludmila M. A1 - Puzyrev, Valery P. A1 - Bragina, Elena Yu A1 - Hudson, Thomas J. A1 - Morin, Charles A1 - Duffy, David L. A1 - Marks, Guy B. A1 - Robertson, Colin F. A1 - Montgomery, Grant W. A1 - Musk, Bill A1 - Thompson, Philip J. A1 - Martin, Nicholas G. A1 - James, Alan A1 - Sleiman, Patrick A1 - Toskala, Elina A1 - Rodriguez, Elke A1 - Fölster-Holst, Regina A1 - Franke, Andre A1 - Lieb, Wolfgang A1 - Gieger, Christian A1 - Heinzmann, Andrea A1 - Rietschel, Ernst A1 - Keil, Thomas A1 - Cichon, Sven A1 - Nöthen, Markus M. A1 - Pennel, Craig E. A1 - Sly, Peter D. A1 - Schmidt, Carsten O. A1 - Matanovic, Anja A1 - Schneider, Valentin A1 - Heinig, Matthias A1 - Hübner, Norbert A1 - Holt, Patrick G. A1 - Lau, Susanne A1 - Kabesch, Michael A1 - Weidinger, Stefan A1 - Hakonarson, Hakon A1 - Ferreira, Manuel A. R. A1 - Laprise, Catherine A1 - Freidin, Maxim B. A1 - Genuneit, Jon A1 - Koppelman, Gerard H. A1 - Melén, Erik A1 - Dizier, Marie-Hélène A1 - Henderson, A. John A1 - Lee, Young Ae T1 - Meta-analysis identifies seven susceptibility loci involved in the atopic march JF - Nature Communications N2 - Eczema often precedes the development of asthma in a disease course called the 'atopic march'. To unravel the genes underlying this characteristic pattern of allergic disease, we conduct a multi-stage genome-wide association study on infantile eczema followed by childhood asthma in 12 populations including 2,428 cases and 17,034 controls. Here we report two novel loci specific for the combined eczema plus asthma phenotype, which are associated with allergic disease for the first time; rs9357733 located in EFHC1 on chromosome 6p12.3 (OR 1.27; P = 2.1 x 10(-8)) and rs993226 between TMTC2 and SLC6A15 on chromosome 12q21.3 (OR 1.58; P = 5.3 x 10(-9)). Additional susceptibility loci identified at genome-wide significance are FLG (1q21.3), IL4/KIF3A (5q31.1), AP5B1/OVOL1 (11q13.1), C11orf30/LRRC32 (11q13.5) and IKZF3 (17q21). We show that predominantly eczema loci increase the risk for the atopic march. Our findings suggest that eczema may play an important role in the development of asthma after eczema. KW - chromosome 11Q13 KW - risk KW - genomewide association KW - hay fever KW - birth cohort KW - filaggrin mutations KW - food allergy KW - juvenile myoclonic epilepsy KW - childhood asthma KW - dermatitis Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-139835 VL - 6 IS - 8804 ER - TY - JOUR A1 - Meir, Michael A1 - Kannapin, Felix A1 - Diefenbacher, Markus A1 - Ghoreishi, Yalda A1 - Kollmann, Catherine A1 - Flemming, Sven A1 - Germer, Christoph-Thomas A1 - Waschke, Jens A1 - Leven, Patrick A1 - Schneider, Reiner A1 - Wehner, Sven A1 - Burkard, Natalie A1 - Schlegel, Nicolas T1 - Intestinal epithelial barrier maturation by enteric glial cells is GDNF-dependent JF - International Journal of Molecular Sciences N2 - Enteric glial cells (EGCs) of the enteric nervous system are critically involved in the maintenance of intestinal epithelial barrier function (IEB). The underlying mechanisms remain undefined. Glial cell line-derived neurotrophic factor (GDNF) contributes to IEB maturation and may therefore be the predominant mediator of this process by EGCs. Using GFAP\(^{cre}\) x Ai14\(^{floxed}\) mice to isolate EGCs by Fluorescence-activated cell sorting (FACS), we confirmed that they synthesize GDNF in vivo as well as in primary cultures demonstrating that EGCs are a rich source of GDNF in vivo and in vitro. Co-culture of EGCs with Caco2 cells resulted in IEB maturation which was abrogated when GDNF was either depleted from EGC supernatants, or knocked down in EGCs or when the GDNF receptor RET was blocked. Further, TNFα-induced loss of IEB function in Caco2 cells and in organoids was attenuated by EGC supernatants or by recombinant GDNF. These barrier-protective effects were blunted when using supernatants from GDNF-deficient EGCs or by RET receptor blockade. Together, our data show that EGCs produce GDNF to maintain IEB function in vitro through the RET receptor. KW - enteric glial cells KW - neurotrophic factors KW - intestinal epithelial barrier KW - GDNF5 KW - RET6 KW - inflammatory bowel disease KW - enteric nervous system KW - gut barrier KW - intercellular junctions Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-258913 SN - 1422-0067 VL - 22 IS - 4 ER - TY - JOUR A1 - Li, Donghai A1 - Shan, Hangyong A1 - Rupprecht, Christoph A1 - Knopf, Heiko A1 - Watanabe, Kenji A1 - Taniguchi, Takashi A1 - Qin, Ying A1 - Tongay, Sefaattin A1 - Nuß, Matthias A1 - Schröder, Sven A1 - Eilenberger, Falk A1 - Höfling, Sven A1 - Schneider, Christian A1 - Brixner, Tobias T1 - Hybridized exciton-photon-phonon states in a transition-metal-dichalcogenide van-der-Waals heterostructure microcavity JF - Physical Review Letters N2 - Excitons in atomically thin transition-metal dichalcogenides (TMDs) have been established as an attractive platform to explore polaritonic physics, owing to their enormous binding energies and giant oscillator strength. Basic spectral features of exciton polaritons in TMD microcavities, thus far, were conventionally explained via two-coupled-oscillator models. This ignores, however, the impact of phonons on the polariton energy structure. Here we establish and quantify the threefold coupling between excitons, cavity photons, and phonons. For this purpose, we employ energy-momentum-resolved photoluminescence and spatially resolved coherent two-dimensional spectroscopy to investigate the spectral properties of a high-quality-factor microcavity with an embedded WSe\(_2\) van-der-Waals heterostructure at room temperature. Our approach reveals a rich multi-branch structure which thus far has not been captured in previous experiments. Simulation of the data reveals hybridized exciton-photon-phonon states, providing new physical insight into the exciton polariton system based on layered TMDs. KW - strong coupling KW - laser spectroscopy KW - transition metal dichalcogenide KW - coherent multidimensional spectroscopy KW - exciton Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-351303 UR - https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.128.087401 SN - 1079-7114 ET - accepted version ER - TY - JOUR A1 - Kim, Seonghoon A1 - Zhang, Bo A1 - Wang, Zhaorong A1 - Fischer, Julian A1 - Brodbeck, Sebastian A1 - Kamp, Martin A1 - Schneider, Christian A1 - Höfling, Sven A1 - Deng, Hui T1 - Coherent Polariton Laser JF - Physical Review X N2 - The semiconductor polariton laser promises a new source of coherent light, which, compared to conventional semiconductor photon lasers, has input-energy threshold orders of magnitude lower. However, intensity stability, a defining feature of a coherent state, has remained poor. Intensity noise many times the shot noise of a coherent state has persisted, attributed to multiple mechanisms that are difficult to separate in conventional polariton systems. The large intensity noise, in turn, limits the phase coherence. Thus, the capability of the polariton laser as a source of coherence light is limited. Here, we demonstrate a polariton laser with shot-noise-limited intensity stability, as expected from a fully coherent state. This stability is achieved by using an optical cavity with high mode selectivity to enforce single-mode lasing, suppress condensate depletion, and establish gain saturation. Moreover, the absence of spurious intensity fluctuations enables the measurement of a transition from exponential to Gaussian decay of the phase coherence of the polariton laser. It suggests large self-interaction energies in the polariton condensate, exceeding the laser bandwidth. Such strong interactions are unique to matter-wave lasers and important for nonlinear polariton devices. The results will guide future development of polariton lasers and nonlinear polariton devices. KW - polariton laser KW - condensed matter physics KW - photonics KW - quantum physics KW - coherent light Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166597 VL - 6 IS - 011026 ER - TY - JOUR A1 - Redlich, Christoph A1 - Lingnau, Benjamin A1 - Holzinger, Steffen A1 - Schlottmann, Elisabeth A1 - Kreinberg, Sören A1 - Schneider, Christian A1 - Kamp, Martin A1 - Höfling, Sven A1 - Wolters, Janik A1 - Reitzenstein, Stephan A1 - Lüdge, Kathy T1 - Mode-switching induced super-thermal bunching in quantum-dot microlasers JF - New Journal of Physics N2 - The super-thermal photon bunching in quantum-dot (QD) micropillar lasers is investigated both experimentally and theoretically via simulations driven by dynamic considerations. Using stochastic multi-mode rate equations we obtain very good agreement between experiment and theory in terms of intensity profiles and intensity-correlation properties of the examined QD micro-laser's emission. Further investigations of the time-dependent emission show that super-thermal photon bunching occurs due to irregular mode-switching events in the bimodal lasers. Our bifurcation analysis reveals that these switchings find their origin in an underlying bistability, such that spontaneous emission noise is able to effectively perturb the two competing modes in a small parameter region. We thus ascribe the observed high photon correlation to dynamical multistabilities rather than quantum mechanical correlations. KW - microlaser KW - nonlinear dynamics KW - correlation properties KW - photon statistics KW - noise and multimode dynamics KW - quantum dot laser Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166286 VL - 18 IS - 063011 ER - TY - JOUR A1 - Nitsche, Wolfgang H. A1 - Kim, Na Young A1 - Roumpos, Georgios A1 - Schneider, Christian A1 - Höfling, Sven A1 - Forchel, Alfred A1 - Yamamoto, Yoshihisa T1 - Spatial correlation of two-dimensional bosonic multimode condensates JF - Physical Review A N2 - The Berezinskii-Kosterlitz-Thouless (BKT) theorem predicts that two-dimensional bosonic condensates exhibit quasi-long-range order which is characterized by a slow decay of the spatial coherence. However previous measurements on exciton-polariton condensates revealed that their spatial coherence can decay faster than allowed under the BKT theory, and different theoretical explanations have already been proposed. Through theoretical and experimental study of exciton-polariton condensates, we show that the fast decay of the coherence can be explained through the simultaneous presence of multiple modes in the condensate. KW - Exciton-polariton condensate KW - Long-range order KW - Microcavity KW - Vortices KW - Systems Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-188897 VL - 93 IS - 5 ER - TY - JOUR A1 - Lundt, Nils A1 - Klembt, Sebastian A1 - Cherotchenko, Evgeniia A1 - Betzold, Simon A1 - Iff, Oliver A1 - Nalitov, Anton V. A1 - Klaas, Martin A1 - Dietrich, Christof P. A1 - Kavokin, Alexey V. A1 - Höfling, Sven A1 - Schneider, Christian T1 - Room-temperature Tamm-plasmon exciton-polaritons with a WSe\(_{2}\) monolayer JF - Nature Communications N2 - Solid-state cavity quantum electrodynamics is a rapidly advancing field, which explores the frontiers of light–matter coupling. Metal-based approaches are of particular interest in this field, as they carry the potential to squeeze optical modes to spaces significantly below the diffraction limit. Transition metal dichalcogenides are ideally suited as the active material in cavity quantum electrodynamics, as they interact strongly with light at the ultimate monolayer limit. Here, we implement a Tamm-plasmon-polariton structure and study the coupling to a monolayer of WSe\(_{2}\), hosting highly stable excitons. Exciton-polariton formation at room temperature is manifested in the characteristic energy–momentum dispersion relation studied in photoluminescence, featuring an anti-crossing between the exciton and photon modes with a Rabi-splitting of 23.5 meV. Creating polaritonic quasiparticles in monolithic, compact architectures with atomic monolayers under ambient conditions is a crucial step towards the exploration of nonlinearities, macroscopic coherence and advanced spinor physics with novel, low-mass bosons. KW - optics and photonics KW - two-dimensional materials KW - electronic properties and materials Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-169470 VL - 7 ER - TY - JOUR A1 - Doerck, Sebastian A1 - Goebel, Kerstin A1 - Weise, Gesa A1 - Schneider-Hohendorf, Tilman A1 - Reinhardt, Michael A1 - Hauff, Peter A1 - Schwab, Nicholas A1 - Linker, Ralf A1 - Maeurer, Mathias A1 - Meuth, Sven G. A1 - Wiendl, Heinz T1 - Temporal Pattern of ICAM-I Mediated Regulatory T Cell Recruitment to Sites of Inflammation in Adoptive Transfer Model of Multiple Sclerosis N2 - Migration of immune cells to the target organ plays a key role in autoimmune disorders like multiple sclerosis (MS). However, the exact underlying mechanisms of this active process during autoimmune lesion pathogenesis remain elusive. To test if pro-inflammatory and regulatory T cells migrate via a similar molecular mechanism, we analyzed the expression of different adhesion molecules, as well as the composition of infiltrating T cells in an in vivo model of MS, adoptive transfer experimental autoimmune encephalomyelitis in rats. We found that the upregulation of ICAM-I and VCAM-I parallels the development of clinical disease onset, but persists on elevated levels also in the phase of clinical remission. However, the composition of infiltrating T cells found in the developing versus resolving lesion phase changed over time, containing increased numbers of regulatory T cells (FoxP3) only in the phase of clinical remission. In order to test the relevance of the expression of cell adhesion molecules, animals were treated with purified antibodies to ICAM-I and VCAM-I either in the phase of active disease or in early remission. Treatment with a blocking ICAM-I antibody in the phase of disease progression led to a milder disease course. However, administration during early clinical remission aggravates clinical symptoms. Treatment with anti-VCAM-I at different timepoints had no significant effect on the disease course. In summary, our results indicate that adhesion molecules are not only important for capture and migration of pro-inflammatory T cells into the central nervous system, but also permit access of anti-inflammatory cells, such as regulatory T cells. Therefore it is likely to assume that intervention at the blood brain barrier is time dependent and could result in different therapeutic outcomes depending on the phase of CNS lesion development. KW - Multiple Sklerose Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-68565 ER - TY - JOUR A1 - Amthor, Matthias A1 - Weißenseel, Sebastian A1 - Fischer, Julian A1 - Kamp, Martin A1 - Schneider, Christian A1 - Höfling, Sven T1 - Electro-optical switching between polariton and cavity lasing in an InGaAs quantum well microcavity N2 - We report on the condensation of microcavity exciton polaritons under optical excitation in a microcavity with four embedded InGaAs quantum wells. The polariton laser is characterized by a distinct nonlinearity in the input-output-characteristics, which is accompanied by a drop of the emission linewidth indicating temporal coherence and a characteristic persisting emission blueshift with increased particle density. The temporal coherence of the device at threshold is underlined by a characteristic drop of the second order coherence function to a value close to 1. Furthermore an external electric field is used to switch between polariton regime, polariton condensate and photon lasing. KW - Quantum-well, -wire and -dot devices KW - Scattering KW - stimulated KW - Resonators KW - Microcavity devices Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-111130 ER - TY - JOUR A1 - Schick, Martin A. A1 - Baar, Wolfgang A1 - Flemming, Sven A1 - Schlegel, Nicolas A1 - Wollborn, Jakob A1 - Held, Christopher A1 - Schneider, Reinhard A1 - Brock, Robert W. A1 - Roewer, Norbert A1 - Wunder, Christian T1 - Sepsis-induced acute kidney injury by standardized colon ascendens stent peritonitis in rats - a simple, reproducible animal model JF - Intensive Care Medicine Experimental N2 - Background Up to 50% of septic patients develop acute kidney injury (AKI). The pathomechanism of septic AKI is poorly understood. Therefore, we established an innovative rodent model to characterize sepsis-induced AKI by standardized colon ascendens stent peritonitis (sCASP). The model has a standardized focus of infection, an intensive care set up with monitoring of haemodynamics and oxygenation resulting in predictable impairment of renal function, AKI parameters as well as histopathology scoring. Methods Anaesthetized rats underwent the sCASP procedure, whereas sham animals were sham operated and control animals were just monitored invasively. Haemodynamic variables and blood gases were continuously measured. After 24 h, animals were reanesthetized; cardiac output (CO), inulin and PAH clearances were measured and later on kidneys were harvested; and creatinine, urea, cystatin C and neutrophil gelatinase-associated lipocalin (NGAL) were analysed. Additional sCASP-treated animals were investigated after 3 and 9 days. Results All sCASP-treated animals survived, whilst ubiquitous peritonitis and significantly deteriorated clinical and macrohaemodynamic sepsis signs after 24 h (MAP, CO, heart rate) were obvious. Blood analyses showed increased lactate and IL-6 levels as well as leucopenia. Urine output, inulin and PAH clearance were significantly decreased in sCASP compared to sham and control. Additionally, significant increase in cystatin C and NGAL was detected. Standard parameters like serum creatinine and urea were elevated and sCASP-induced sepsis increased significantly in a time-dependent manner. The renal histopathological score of sCASP-treated animals deteriorated after 3 and 9 days. Conclusions The presented sCASP method is a standardized, reliable and reproducible method to induce septic AKI. The intensive care set up, continuous macrohaemodynamic and gas exchange monitoring, low mortality rate as well as the opportunity of detailed analyses of kidney function and impairments are advantages of this setup. Thus, our described method may serve as a new standard for experimental investigations of septic AKI. KW - CASP KW - animal model KW - acute kidney injury KW - sepsis Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126111 VL - 2 IS - 34 ER - TY - JOUR A1 - Schick, Martin Alexander A1 - Baar, Wolfgang A1 - Bruno, Raphael Romano A1 - Wollborn, Jakob A1 - Held, Christopher A1 - Schneider, Reinhard A1 - Flemming, Sven A1 - Schlegel, Nicolas A1 - Roewer, Norbert A1 - Neuhaus, Winfried A1 - Wunder, Christian T1 - Balanced hydroxyethylstarch (HES 130/0.4) impairs kidney function in-vivo without inflammation JF - PLoS One N2 - Volume therapy is a standard procedure in daily perioperative care, and there is an ongoing discussion about the benefits of colloid resuscitation with hydroxyethylstarch (HES). In sepsis HES should be avoided due to a higher risk for acute kidney injury (AKI). Results of the usage of HES in patients without sepsis are controversial. Therefore we conducted an animal study to evaluate the impact of 6% HES 130/0.4 on kidney integrity with sepsis or under healthy conditions Sepsis was induced by standardized Colon Ascendens Stent Peritonitis (sCASP). sCASP-group as well as control group (C) remained untreated for 24 h. After 18 h sCASP+HES group (sCASP+VOL) and control+HES (C+VOL) received 50 ml/KG balanced 6% HES (VOL) 130/0.4 over 6h. After 24h kidney function was measured via Inulin- and PAH-Clearance in re-anesthetized rats, and serum urea, creatinine (crea), cystatin C and Neutrophil gelatinase-associated lipocalin (NGAL) as well as histopathology were analysed. In vitro human proximal tubule cells (PTC) were cultured +/- lipopolysaccharid (LPS) and with 0.1–4.0% VOL. Cell viability was measured with XTT-, cell toxicity with LDH-test. sCASP induced severe septic AKI demonstrated divergent results regarding renal function by clearance or creatinine measure focusing on VOL. Soleley HES (C+VOL) deteriorated renal function without sCASP. Histopathology revealed significantly derangements in all HES groups compared to control. In vitro LPS did not worsen the HES induced reduction of cell viability in PTC cells. For the first time, we demonstrated, that application of 50 ml/KG 6% HES 130/0.4 over 6 hours induced AKI without inflammation in vivo. Severity of sCASP induced septic AKI might be no longer susceptible to the way of volume expansion KW - colloids KW - kidneys KW - histopathology KW - blood KW - creatinine KW - sepsis KW - urine KW - inflammation Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126068 VL - 10 IS - 9 ER - TY - JOUR A1 - Winkler, Karol A1 - Fischer, Julian A1 - Schade, Anne A1 - Amthor, Matthias A1 - Dall, Robert A1 - Geßler, Jonas A1 - Emmerling, Monika A1 - Ostrovskaya, Elena A. A1 - Kamp, Martin A1 - Schneider, Christian A1 - Höfling, Sven T1 - A polariton condensate in a photonic crystal potential landscape JF - New Journal of Physics N2 - The possibility of investigating macroscopic coherent quantum states in polariton condensates and of engineering polariton landscapes in semiconductors has triggered interest in using polaritonic systems to simulate complex many-body phenomena. However, advanced experiments require superior trapping techniques that allow for the engineering of periodic and arbitrary potentials with strong on-site localization, clean condensate formation, and nearest-neighbor coupling. Here we establish a technology that meets these demands and enables strong, potentially tunable trapping without affecting the favorable polariton characteristics. The traps are based on a locally elongated microcavity which can be formed by standard lithography. We observe polariton condensation with non-resonant pumping in single traps and photonic crystal square lattice arrays. In the latter structures, we observe pronounced energy bands, complete band gaps, and spontaneous condensation at the M-point of the Brillouin zone. Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125050 VL - 17 ER - TY - JOUR A1 - Maier, Sebastian A1 - Gold, Peter A1 - Forchel, Alfred A1 - Gregersen, Niels A1 - Mork, Jesper A1 - Höfling, Sven A1 - Schneider, Christian A1 - Kamp, Martin T1 - Bright single photon source based on self-aligned quantum dot-cavity systems JF - Optics Express N2 - We report on a quasi-planar quantum-dot-based single-photon source that shows an unprecedented high extraction efficiency of 42% without complex photonic resonator geometries or post-growth nanofabrication. This very high efficiency originates from the coupling of the photons emitted by a quantum dot to a Gaussian shaped nanohill defect that naturally arises during epitaxial growth in a self-aligned manner. We investigate the morphology of these defects and characterize the photonic operation mechanism. Our results show that these naturally arising coupled quantum dot-defects provide a new avenue for efficient (up to 42% demonstrated) and pure (g(2)(0) value of 0.023) single-photon emission. KW - photon statistics KW - quantum communications KW - resonators KW - quantum-well -wire and -dot devices Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-119801 SN - 1094-4087 VL - 22 IS - 7 ER - TY - JOUR A1 - Yu, Leo A1 - Natarajan, Chandra M. A1 - Horikiri, Tomoyuki A1 - Langrock, Carsten A1 - Pelc, Jason S. A1 - Tanner, Michael G. A1 - Abe, Eisuke A1 - Maier, Sebastian A1 - Schneider, Christian A1 - Höfling, Sven A1 - Kamp, Martin A1 - Hadfield, Robert H. A1 - Fejer, Martin M. A1 - Yamamoto, Yoshihisa T1 - Two-photon interference at telecom wavelengths for time-bin-encoded single photons from quantum-dot spin qubits JF - Nature Communications N2 - Practical quantum communication between remote quantum memories rely on single photons at telecom wavelengths. Although spin-photon entanglement has been demonstrated in atomic and solid-state qubit systems, the produced single photons at short wavelengths and with polarization encoding are not suitable for long-distance communication, because they suffer from high propagation loss and depolarization in optical fibres. Establishing entanglement between remote quantum nodes would further require the photons generated from separate nodes to be indistinguishable. Here, we report the observation of correlations between a quantum-dot spin and a telecom single photon across a 2-km fibre channel based on time-bin encoding and background-free frequency downconversion. The downconverted photon at telecom wavelengths exhibits two-photon interference with another photon from an independent source, achieving a mean wavepacket overlap of greater than 0.89 despite their original wavelength mismatch (900 and 911 nm). The quantum-networking operations that we demonstrate will enable practical communication between solid-state spin qubits across long distances. KW - atom KW - 1550 nm KW - up-conversion KW - heralded entanglement KW - emission KW - interface KW - generation KW - communication KW - downconversion Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-138677 VL - 6 ER - TY - JOUR A1 - Manchia, Mirko A1 - Adli, Mazda A1 - Akula, Nirmala A1 - Arda, Raffaella A1 - Aubry, Jean-Michel A1 - Backlund, Lena A1 - Banzato, Claudio E. M. A1 - Baune, Bernhard T. A1 - Bellivier, Frank A1 - Bengesser, Susanne A1 - Biernacka, Joanna M. A1 - Brichant-Petitjean, Clara A1 - Bui, Elise A1 - Calkin, Cynthia V. A1 - Cheng, Andrew Tai Ann A1 - Chillotti, Caterina A1 - Cichon, Sven A1 - Clark, Scott A1 - Czerski, Piotr M. A1 - Dantas, Clarissa A1 - Del Zompo, Maria A1 - DePaulo, J. Raymond A1 - Detera-Wadleigh, Sevilla D. A1 - Etain, Bruno A1 - Falkai, Peter A1 - Frisén, Louise A1 - Frye, Mark A. A1 - Fullerton, Jan A1 - Gard, Sébastien A1 - Garnham, Julie A1 - Goes, Fernando S. A1 - Grof, Paul A1 - Gruber, Oliver A1 - Hashimoto, Ryota A1 - Hauser, Joanna A1 - Heilbronner, Urs A1 - Hoban, Rebecca A1 - Hou, Liping A1 - Jamain, Stéphane A1 - Kahn, Jean-Pierre A1 - Kassem, Layla A1 - Kato, Tadafumi A1 - Kelsoe, John R. A1 - Kittel-Schneider, Sarah A1 - Kliwicki, Sebastian A1 - Kuo, Po-Hsiu A1 - Kusumi, Ichiro A1 - Laje, Gonzalo A1 - Lavebratt, Catharina A1 - Leboyer, Marion A1 - Leckband, Susan G. A1 - López Jaramillo, Carlos A. A1 - Maj, Mario A1 - Malafosse, Alain A1 - Martinsson, Lina A1 - Masui, Takuya A1 - Mitchell, Philip B. A1 - Mondimore, Frank A1 - Monteleone, Palmiero A1 - Nallet, Audrey A1 - Neuner, Maria A1 - Novák, Tomás A1 - O'Donovan, Claire A1 - Ösby, Urban A1 - Ozaki, Norio A1 - Perlis, Roy H. A1 - Pfennig, Andrea A1 - Potash, James B. A1 - Reich-Erkelenz, Daniela A1 - Reif, Andreas A1 - Reininghaus, Eva A1 - Richardson, Sara A1 - Rouleau, Guy A. A1 - Rybakowski, Janusz K. A1 - Schalling, Martin A1 - Schofield, Peter R. A1 - Schubert, Oliver K. A1 - Schweizer, Barbara A1 - Seemüller, Florian A1 - Grigoroiu-Serbanescu, Maria A1 - Severino, Giovanni A1 - Seymour, Lisa R. A1 - Slaney, Claire A1 - Smoller, Jordan W. A1 - Squassina, Alessio A1 - Stamm, Thomas A1 - Steele, Jo A1 - Stopkova, Pavla A1 - Tighe, Sarah K. A1 - Tortorella, Alfonso A1 - Turecki, Gustavo A1 - Wray, Naomi R. A1 - Wright, Adam A1 - Zandi, Peter P. A1 - Zilles, David A1 - Bauer, Michael A1 - Rietschel, Marcella A1 - McMahon, Francis J. A1 - Schulze, Thomas G. A1 - Alda, Martin T1 - Assessment of Response to Lithium Maintenance Treatment in Bipolar Disorder: A Consortium on Lithium Genetics (ConLiGen) Report JF - PLoS ONE N2 - Objective: The assessment of response to lithium maintenance treatment in bipolar disorder (BD) is complicated by variable length of treatment, unpredictable clinical course, and often inconsistent compliance. Prospective and retrospective methods of assessment of lithium response have been proposed in the literature. In this study we report the key phenotypic measures of the "Retrospective Criteria of Long-Term Treatment Response in Research Subjects with Bipolar Disorder" scale currently used in the Consortium on Lithium Genetics (ConLiGen) study. Materials and Methods: Twenty-nine ConLiGen sites took part in a two-stage case-vignette rating procedure to examine inter-rater agreement [Kappa (\(\kappa\))] and reliability [intra-class correlation coefficient (ICC)] of lithium response. Annotated first-round vignettes and rating guidelines were circulated to expert research clinicians for training purposes between the two stages. Further, we analyzed the distributional properties of the treatment response scores available for 1,308 patients using mixture modeling. Results: Substantial and moderate agreement was shown across sites in the first and second sets of vignettes (\(\kappa\) = 0.66 and \(\kappa\) = 0.54, respectively), without significant improvement from training. However, definition of response using the A score as a quantitative trait and selecting cases with B criteria of 4 or less showed an improvement between the two stages (\(ICC_1 = 0.71\) and \(ICC_2 = 0.75\), respectively). Mixture modeling of score distribution indicated three subpopulations (full responders, partial responders, non responders). Conclusions: We identified two definitions of lithium response, one dichotomous and the other continuous, with moderate to substantial inter-rater agreement and reliability. Accurate phenotypic measurement of lithium response is crucial for the ongoing ConLiGen pharmacogenomic study. KW - age KW - observer agreement KW - prophylactic lithium KW - mapping susceptibility genes KW - mood disorders KW - onset KW - association KW - reliability KW - morality KW - illness Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-130938 VL - 8 IS - 6 ER - TY - JOUR A1 - Rau, Markus A1 - Heindel, Tobias A1 - Unsleber, Sebastian A1 - Braun, Tristan A1 - Fischer, Julian A1 - Frick, Stefan A1 - Nauerth, Sebastian A1 - Schneider, Christian A1 - Vest, Gwenaelle A1 - Reitzenstein, Stephan A1 - Kamp, Martin A1 - Forchel, Alfred A1 - Höfling, Sven A1 - Weinfurter, Harald T1 - Free space quantum key distribution over 500 meters using electrically driven quantum dot single-photon sources-a proof of principle experiment JF - New Journal of Physics N2 - Highly efficient single-photon sources (SPS) can increase the secure key rate of quantum key distribution (QKD) systems compared to conventional attenuated laser systems. Here we report on a free space QKD test using an electrically driven quantum dot single-photon source (QD SPS) that does not require a separate laser setup for optical pumping and thus allows for a simple and compact SPS QKD system. We describe its implementation in our 500 m free space QKD system in downtown Munich. Emulating a BB84 protocol operating at a repetition rate of 125 MHz, we could achieve sifted key rates of 5-17 kHz with error ratios of 6-9% and g((2))(0)-values of 0.39-0.76. KW - QKD KW - electrically driven KW - free space KW - quantum dots KW - quantum key distribution Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-116760 VL - 16 IS - 043003 ER - TY - JOUR A1 - Wallmann-Sperlich, Birgit A1 - Bucksch, Jens A1 - Schneider, Sven A1 - Froboese, Ingo T1 - Socio-demographic, behavioural and cognitive correlates of work-related sitting time in German men and women N2 - Background: Sitting time is ubiquitous for most adults in developed countries and is most prevalent in three domains: in the workplace, during transport and during leisure time. The correlates of prolonged sitting time in workplace settings are not well understood. Therefore, the aim of this study was to examine the gender-specific associations between the socio-demographic, behavioural and cognitive correlates of work-related sitting time. Methods: A cross-sectional sample of working German adults (n = 1515; 747 men; 43.5 ± 11.0 years) completed questionnaires regarding domain-specific sitting times and physical activity (PA) and answered statements concerning beliefs about sitting. To identify gender-specific correlates of work-related sitting time, we used a series of linear regressions. Results: The overall median was 2 hours of work-related sitting time/day. Regression analyses showed for men (β = −.43) and for women (β = −.32) that work-related PA was negatively associated with work-related sitting time, but leisure-related PA was not a significant correlate. For women only, transport-related PA (β = −.07) was a negative correlate of work-related sitting time, suggesting increased sitting times during work with decreased PA in transport. Education and income levels were positively associated, and in women only, age (β = −.14) had a negative correlation with work-related sitting time. For both genders, TV-related sitting time was negatively associated with work-related sitting time. The only association with cognitive correlates was found in men for the belief ‘Sitting for long periods does not matter to me’ (β = .10) expressing a more positive attitude towards sitting with increasing sitting durations. Conclusions: The present findings show that in particular, higher educated men and women as well as young women are high-risk groups to target for reducing prolonged work-related sitting time. In addition, our findings propose considering increasing transport-related PA, especially in women, as well as promoting recreation-related PA in conjunction with efforts to reduce long work-related sitting times. KW - Physical activity KW - Sedentary behaviour KW - Health promotion KW - Health-determinants KW - Sitting/standing KW - Sex KW - Association KW - Domain-specific approach KW - Correlates Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-111017 ER - TY - JOUR A1 - Schlottmann, Elisabeth A1 - Schicke, David A1 - Krüger, Felix A1 - Lingnau, Benjamin A1 - Schneider, Christian A1 - Höfling, Sven A1 - Lüdge, Kathy A1 - Porte, Xavier A1 - Reitzenstein, Stephan T1 - Stochastic polarization switching induced by optical injection in bimodal quantum-dot micropillar lasers JF - Optics Express N2 - Mutual coupling and injection locking of semiconductor lasers is of great interest in non-linear dynamics and its applications for instance in secure data communication and photonic reservoir computing. Despite its importance, it has hardly been studied in microlasers operating at mu W light levels. In this context, vertically emitting quantum dot micropillar lasers are of high interest. Usually, their light emission is bimodal, and the gain competition of the associated linearly polarized fundamental emission modes results in complex switching dynamics. We report on selective optical injection into either one of the two fundamental mode components of a bimodal micropillar laser. Both modes can lock to the master laser and influence the non-injected mode by reducing the available gain. We demonstrate that the switching dynamics can be tailored externally via optical injection in very good agreement with our theory based on semi-classical rate equations. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement KW - Nonlinear Dynamics KW - Bistability KW - Generation KW - Subject KW - Regimes KW - Physics KW - Vcsels Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-228603 VL - 27 IS - 20 ER - TY - JOUR A1 - He, Yu-Ming A1 - Iff, Oliver A1 - Lundt, Nils A1 - Baumann, Vasilij A1 - Davanco, Marcelo A1 - Srinivasan, Kartik A1 - Höfling, Sven A1 - Schneider, Christian T1 - Cascaded emission of single photons from the biexciton in monolayered WSe\(_{2}\) JF - Nature Communications N2 - Monolayers of transition metal dichalcogenide materials emerged as a new material class to study excitonic effects in solid state, as they benefit from enormous Coulomb correlations between electrons and holes. Especially in WSe\(_{2}\), sharp emission features have been observed at cryogenic temperatures, which act as single photon sources. Tight exciton localization has been assumed to induce an anharmonic excitation spectrum; however, the evidence of the hypothesis, namely the demonstration of a localized biexciton, is elusive. Here we unambiguously demonstrate the existence of a localized biexciton in a monolayer of WSe\(_{2}\), which triggers an emission cascade of single photons. The biexciton is identified by its time-resolved photoluminescence, superlinearity and distinct polarization in micro-photoluminescence experiments. We evidence the cascaded nature of the emission process in a cross-correlation experiment, which yields a strong bunching behaviour. Our work paves the way to a new generation of quantum optics experiments with two-dimensional semiconductors. KW - lasers KW - LED KW - quantum dots KW - light sources Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-169363 VL - 7 ER - TY - JOUR A1 - Kochereshko, Vladimir P. A1 - Durnev, Mikhail V. A1 - Besombes, Lucien A1 - Mariette, Henri A1 - Sapega, Victor F. A1 - Askitopoulos, Alexis A1 - Savenko, Ivan G. A1 - Liew, Timothy C. H. A1 - Shelykh, Ivan A. A1 - Platonov, Alexey V. A1 - Tsintzos, Simeon I. A1 - Hatzopoulos, Z. A1 - Savvidis, Pavlos G. A1 - Kalevich, Vladimir K. A1 - Afanasiev, Mikhail M. A1 - Lukoshkin, Vladimir A. A1 - Schneider, Christian A1 - Amthor, Matthias A1 - Metzger, Christian A1 - Kamp, Martin A1 - Hoefling, Sven A1 - Lagoudakis, Pavlos A1 - Kavokin, Alexey T1 - Lasing in Bose-Fermi mixtures JF - Scientific Reports N2 - Light amplification by stimulated emission of radiation, well-known for revolutionising photonic science, has been realised primarily in fermionic systems including widely applied diode lasers. The prerequisite for fermionic lasing is the inversion of electronic population, which governs the lasing threshold. More recently, bosonic lasers have also been developed based on Bose-Einstein condensates of exciton-polaritons in semiconductor microcavities. These electrically neutral bosons coexist with charged electrons and holes. In the presence of magnetic fields, the charged particles are bound to their cyclotron orbits, while the neutral exciton-polaritons move freely. We demonstrate how magnetic fields affect dramatically the phase diagram of mixed Bose-Fermi systems, switching between fermionic lasing, incoherent emission and bosonic lasing regimes in planar and pillar microcavities with optical and electrical pumping. We collected and analyzed the data taken on pillar and planar microcavity structures at continuous wave and pulsed optical excitation as well as injecting electrons and holes electronically. Our results evidence the transition from a Bose gas to a Fermi liquid mediated by magnetic fields and light-matter coupling. KW - Bose-Fermi KW - magnetic fields KW - Bose gas KW - Fermi liquid KW - light-matter coupling Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-168152 VL - 6 IS - 20091 ER - TY - JOUR A1 - Jahnke, Frank A1 - Gies, Christopher A1 - Aßmann, Marc A1 - Bayer, Manfred A1 - Leymann, H.A.M. A1 - Foerster, Alexander A1 - Wiersig, Jan A1 - Schneider, Christian A1 - Kamp, Martin A1 - Höfling, Sven T1 - Giant photon bunching, superradiant pulse emission and excitation trapping in quantum-dot nanolasers JF - Nature Communications N2 - Light is often characterized only by its classical properties, like intensity or coherence. When looking at its quantum properties, described by photon correlations, new information about the state of the matter generating the radiation can be revealed. In particular the difference between independent and entangled emitters, which is at the heart of quantum mechanics, can be made visible in the photon statistics of the emitted light. The well-studied phenomenon of superradiance occurs when quantum–mechanical correlations between the emitters are present. Notwithstanding, superradiance was previously demonstrated only in terms of classical light properties. Here, we provide the missing link between quantum correlations of the active material and photon correlations in the emitted radiation. We use the superradiance of quantum dots in a cavity-quantum electrodynamics laser to show a direct connection between superradiant pulse emission and distinctive changes in the photon correlation function. This directly demonstrates the importance of quantum–mechanical correlations and their transfer between carriers and photons in novel optoelectronic devices. KW - photon bunching KW - quantum mechanics KW - superradiant pulse emission Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166144 VL - 7 IS - 11540 ER - TY - JOUR A1 - Lee, Chang-Min A1 - Lim, Hee-Jin A1 - Schneider, Christian A1 - Maier, Sebastian A1 - Höfling, Sven A1 - Kamp, Martin A1 - Lee, Yong-Hee T1 - Efficient single photon source based on \(\mu\)-fibre-coupled tunable microcavity JF - Scientific Reports N2 - Efficient and fast on-demand single photon sources have been sought after as critical components of quantum information science. We report an efficient and tunable single photon source based on an InAs quantum dot (QD) embedded in a photonic crystal cavity coupled with a highly curved \(\mu\)-fibre. Exploiting evanescent coupling between the \(\mu\)-fibre and the cavity, a high collection efficiency of 23% and Purcell-enhanced spontaneous emissions are observed. In our scheme, the spectral position of a resonance can be tuned by as much as 1.5 nm by adjusting the contact position of the \(\mu\)-fibre, which increases the spectral coupling probability between the QD and the cavity mode. Taking advantage of the high photon count rate and the tunability, the collection efficiencies and the decay rates are systematically investigated as a function of the QD-cavity detuning. KW - tapers KW - semiconductor quantum dots KW - crystal KW - nanowire KW - generation KW - nanoactivity KW - mode KW - emission Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-145835 VL - 5 IS - 14309 ER - TY - JOUR A1 - Wurdack, Matthias A1 - Lundt, Nils A1 - Klaas, Martin A1 - Baumann, Vasilij A1 - Kavokin, Alexey V. A1 - Höfling, Sven A1 - Schneider, Christian T1 - Observation of hybrid Tamm-plasmon exciton-polaritons with GaAs quantum wells and a MoSe\(_{2}\) monolayer JF - Nature Communications N2 - Strong light matter coupling between excitons and microcavity photons, as described in the framework of cavity quantum electrodynamics, leads to the hybridization of light and matter excitations. The regime of collective strong coupling arises, when various excitations from different host media are strongly coupled to the same optical resonance. This leads to a well-controllable admixture of various matter components in three hybrid polariton modes. Here, we study a cavity device with four embedded GaAs quantum wells hosting excitons that are spectrally matched to the A-valley exciton resonance of a MoSe\(_{2}\) monolayer. The formation of hybrid polariton modes is evidenced in momentum resolved photoluminescence and reflectivity studies. We describe the energy and k-vector distribution of exciton-polaritons along the hybrid modes by a thermodynamic model, which yields a very good agreement with the experiment. KW - two-dimensional materials KW - microresonators KW - nanophotonics and plasmonics KW - cavity device KW - strong coupling Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-170480 VL - 8 IS - 259 ER - TY - JOUR A1 - Sitter, Magdalena A1 - Schlesinger, Tobias A1 - Reinhold, Ann-Kristin A1 - Scholler, Axel A1 - Heymann, Christian von A1 - Welfle, Sabine A1 - Bartmann, Catharina A1 - Wöckel, Achim A1 - Kleinschmidt, Stefan A1 - Schneider, Sven A1 - Gottschalk, André A1 - Greve, Susanne A1 - Wermelt, Julius Z. A1 - Wiener, Roland A1 - Schulz, Frank A1 - Chappell, Daniel A1 - Brunner, Maya A1 - Neumann, Claudia A1 - Meybohm, Patrick A1 - Kranke, Peter T1 - COVID-19 in der geburtshilflichen Anästhesie: Prospektive Erfassung von SARS-CoV-2-Infektionen zum Zeitpunkt der Geburt sowie des peripartalen Verlaufs SARS-CoV-2-positiver Schwangerer JF - Der Anaesthesist N2 - Hintergrund Im Rahmen der Pandemie des SARS-CoV-2-Virus erlangte das Patientenkollektiv der Schwangeren früh Aufmerksamkeit. Initial wurde angesichts sich früh abzeichnender Krankheitsfälle bei jüngeren Patienten mit einem erheblichen Aufkommen peripartal zu betreuender, COVID-19-positiver Schwangerer gerechnet. Ziel der Arbeit Diese Arbeit vermittelt einen Einblick in die SARS-CoV-2-Infektionszahlen im Rahmen der geburtshilflichen Anästhesie zu Beginn der Pandemie sowie während der zweiten Infektionswelle in Deutschland. Methoden Über das COALA-Register (COVID-19 related Obstetric Anaesthesia Longitudinal Assessment-Registry) wurden sowohl von März bis Mai 2020 als auch von Oktober 2020 bis Februar 2021 in Deutschland und der Schweiz wöchentlich prospektiv Daten zu Verdachts- und bestätigten SARS-CoV-2-Fällen bei Schwangeren zum Zeitpunkt der Geburt erhoben. Betrachtet wurden die Verteilung dieser auf die Anzahl der Geburten, Zentren und Erhebungswochen sowie mütterliche Charakteristika und Krankheitsverläufe. Ergebnisse Neun Zentren haben im Verlauf 44 SARS-CoV-2-positive Schwangere zum Zeitpunkt der Geburt bei 7167 Geburten (0,6 %) gemeldet (3 Fälle auf 2270 Geburten (0,4 %) und 41 Fälle auf 4897 Geburten (0,8 %)). Berichtet wurden 2 schwere COVID-19-Verläufe (n = 1 mit Todesfolge nach ECMO, n = 1 mit ECMO überlebt). Bei 28 (68 %) Patientinnen verlief die Infektion asymptomatisch. Ein Neugeborenes wurde im Verlauf positiv auf SARS-CoV‑2 getestet. Schlussfolgerung Mithilfe des Registers konnte das Auftreten von Fällen zu Beginn der Pandemie zeitnah eingeschätzt werden. Es traten sporadisch Verdachtsfälle bzw. bestätigte Fälle auf. Aufgrund fehlender flächendeckender Testung muss aber von einer Dunkelziffer asymptomatischer Fälle ausgegangen werden. Während der zweiten Infektionswelle wurden 68 % asymptomatische Fälle gemeldet. Jedoch kann es bei jungen, gesunden Patientinnen ohne das Vorliegen typischer Risikofaktoren zu schwerwiegenden Verläufen kommen. KW - ECMO-Therapie KW - Geburtshilfe KW - Geburtshilfliche Intensivmedizin KW - COVID-19-Pademie KW - Infektionswellen Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-264878 SN - 1432-055X VL - 71 IS - 6 ER -