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 - 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 -