TY  - JOUR
A1  - Thierschmann, H.
A1  - Henke, M.
A1  - Knorr, J.
A1  - Maier, L.
A1  - Heyn, C.
A1  - Hansen, W.
A1  - Buhmann, H.
A1  - Molenkamp, L. W.
T1  - Diffusion thermopower of a serial double quantum dot
JF  - New Journal of Physics
N2  - We have experimentally studied the diffusion thermopower of a serial double quantum dot, defined electrostatically in a GaAs/AlGaAs heterostructure. We present the thermopower stability diagram for a temperature difference 1T = (20±10)mK across the device and find a maximum thermovoltage signal of several μV in the vicinity of the triple points. Along a constant energy axis in this regime, the data show a characteristic pattern which is in agreement with Mott’s relation and can be well understood within a model of sequential transport.
KW  - quantum dot
Y1  - 2013
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-129714
VL  - 15
IS  - 123010
ER  - 
TY  - JOUR
A1  - Thierschmann, H
A1  - Arnold, F
A1  - Mittermüller, M
A1  - Maier, L
A1  - Heyn, C
A1  - Hansen, W
A1  - Buhmann, H
A1  - Molenkamp, L W
T1  - Thermal gating of charge currents with Coulomb coupled quantum dots
JF  - New Journal of Physics
N2  - We have observed thermal gating, i.e. electrostatic gating induced by hot electrons. The effect occurs in a device consisting of two capacitively coupled quantum dots. The double dot system is coupled to a hot electron reservoir on one side (QD1), while the conductance of the second dot (QD2) is monitored. When a bias across QD2 is applied we observe a current which is strongly dependent on the temperature of the heat reservoir. This current can be either enhanced or suppressed, depending on the relative energetic alignment of the QD levels. Thus, the system can be used to control a charge current by hot electrons.
KW  - oscillations
KW  - physics
KW  - quantum dot systems
KW  - Coulomb interaction
KW  - thermal gating
KW  - three terminal device
KW  - thermoelectrics
KW  - energy
KW  - thermopower
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-145196
VL  - 17
IS  - 113003
ER  - 
TY  - JOUR
A1  - Krüger, H.-P.
A1  - Bonerad, E. M.
A1  - Dennler, H. J.
A1  - Dunkl, E.
A1  - Friese, H. J.
A1  - Hain, C.
A1  - Kazenwadel, J.
A1  - Kohnen, Ralf
A1  - Maier, W.
A1  - Menzel, M.
T1  - Speech chronemics in drug evaluation
N2  - No abstract available
Y1  - 1992
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-41213
ER  - 
TY  - JOUR
A1  - Oostinga, Jeroen B.
A1  - Maier, Luis
A1  - Schüffelgen, Peter
A1  - Knott, Daniel
A1  - Ames, Christopher
A1  - Brüne, Christoph
A1  - Tkachov, Grigory
A1  - Buhmann, Hartmut
A1  - Molenkamp, Laurens W.
T1  - Josephson Supercurrent through the Topological Surface States of Strained Bulk HgTe
JF  - Physical Review X
N2  - Strained bulk HgTe is a three-dimensional topological insulator, whose surface electrons have a high mobility (~ 30 000 cm\(^2\)=Vs), while its bulk is effectively free of mobile charge carriers. These properties enable a study of transport through its unconventional surface states without being hindered by a parallel bulk conductance. Here, we show transport experiments on HgTe-based Josephson junctions to investigate the appearance of the predicted Majorana states at the interface between a topological insulator and a superconductor. Interestingly, we observe a dissipationless supercurrent flow through the topological surface states of HgTe. The current-voltage characteristics are hysteretic at temperatures below 1 K, with critical supercurrents of several microamperes. Moreover, we observe a magnetic-field-induced Fraunhofer pattern of the critical supercurrent, indicating a dominant \(2\pi\)-periodic Josephson effect in the unconventional surface states. Our results show that strained bulk HgTe is a promising material system to get a better understanding of the Josephson effect in topological surface states, and to search for the manifestation of zero-energy Majorana states in transport experiments.
KW  - topological insulators
KW  - mesoscopics
KW  - superconductivity
Y1  - 2013
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-129834
VL  - 3
IS  - 021007
ER  - 
TY  - JOUR
A1  - Weber, Heike
A1  - Scholz, Claus Jürgen
A1  - Domschke, Katharina
A1  - Baumann, Christian
A1  - Klauke, Benedikt
A1  - Jacob, Christian P.
A1  - Maier, Wolfgang
A1  - Fritze, Jürgen
A1  - Bandelow, Borwin
A1  - Zwanzger, Peter Michael
A1  - Lang, Thomas
A1  - Fehm, Lydia
A1  - Ströhle, Andreas
A1  - Hamm, Alfons
A1  - Gerlach, Alexander L.
A1  - Alpers, Georg W.
A1  - Kircher, Tilo
A1  - Wittchen, Hans-Ulrich
A1  - Arolt, Volker
A1  - Pauli, Paul
A1  - Deckert, Jürgen
A1  - Reif, Andreas
T1  - Gender Differences in Associations of Glutamate Decarboxylase 1 Gene (GAD1) Variants with Panic Disorder
N2  - Background: Panic disorder is common (5% prevalence) and females are twice as likely to be affected as males. The heritable component of panic disorder is estimated at 48%. Glutamic acid dehydrogenase GAD1, the key enzyme for the synthesis of the inhibitory and anxiolytic neurotransmitter GABA, is supposed to influence various mental disorders, including mood and anxiety disorders. In a recent association study in depression, which is highly comorbid with panic disorder, GAD1 risk allele associations were restricted to females. Methodology/Principal Findings: Nineteen single nucleotide polymorphisms (SNPs) tagging the common variation in GAD1 were genotyped in two independent gender and age matched case-control samples (discovery sample n = 478; replication sample n = 584). Thirteen SNPs passed quality control and were examined for gender-specific enrichment of risk alleles associated with panic disorder by using logistic regression including a genotype6gender interaction term. The latter was found to be nominally significant for four SNPs (rs1978340, rs3762555, rs3749034, rs2241165) in the discovery sample; of note, the respective minor/risk alleles were associated with panic disorder only in females. These findings were not confirmed in the replication sample; however, the genotype6gender interaction of rs3749034 remained significant in the combined sample. Furthermore, this polymorphism showed a nominally significant association with the Agoraphobic Cognitions Questionnaire sum score. Conclusions/Significance: The present study represents the first systematic evaluation of gender-specific enrichment of risk alleles of the common SNP variation in the panic disorder candidate gene GAD1. Our tentative results provide a possible explanation for the higher susceptibility of females to panic disorder.
KW  - Medizin
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-75830
ER  - 
TY  - JOUR
A1  - Dumont, Martine
A1  - Weber-Lassalle, Nana
A1  - Joly-Beauparlant, Charles
A1  - Ernst, Corinna
A1  - Droit, Arnaud
A1  - Feng, Bing-Jian
A1  - Dubois, Stéphane
A1  - Collin-Deschesnes, Annie-Claude
A1  - Soucy, Penny
A1  - Vallée, Maxime
A1  - Fournier, Frédéric
A1  - Lemaçon, Audrey
A1  - Adank, Muriel A.
A1  - Allen, Jamie
A1  - Altmüller, Janine
A1  - Arnold, Norbert
A1  - Ausems, Margreet G. E. M.
A1  - Berutti, Riccardo
A1  - Bolla, Manjeet K.
A1  - Bull, Shelley
A1  - Carvalho, Sara
A1  - Cornelissen, Sten
A1  - Dufault, Michael R.
A1  - Dunning, Alison M.
A1  - Engel, Christoph
A1  - Gehrig, Andrea
A1  - Geurts-Giele, Willemina R. R.
A1  - Gieger, Christian
A1  - Green, Jessica
A1  - Hackmann, Karl
A1  - Helmy, Mohamed
A1  - Hentschel, Julia
A1  - Hogervorst, Frans B. L.
A1  - Hollestelle, Antoinette
A1  - Hooning, Maartje J.
A1  - Horváth, Judit
A1  - Ikram, M. Arfan
A1  - Kaulfuß, Silke
A1  - Keeman, Renske
A1  - Kuang, Da
A1  - Luccarini, Craig
A1  - Maier, Wolfgang
A1  - Martens, John W. M.
A1  - Niederacher, Dieter
A1  - Nürnberg, Peter
A1  - Ott, Claus-Eric
A1  - Peters, Annette
A1  - Pharoah, Paul D. P.
A1  - Ramirez, Alfredo
A1  - Ramser, Juliane
A1  - Riedel-Heller, Steffi
A1  - Schmidt, Gunnar
A1  - Shah, Mitul
A1  - Scherer, Martin
A1  - Stäbler, Antje
A1  - Strom, Tim M.
A1  - Sutter, Christian
A1  - Thiele, Holger
A1  - van Asperen, Christi J.
A1  - van der Kolk, Lizet
A1  - van der Luijt, Rob B.
A1  - Volk, Alexander E.
A1  - Wagner, Michael
A1  - Waisfisz, Quinten
A1  - Wang, Qin
A1  - Wang-Gohrke, Shan
A1  - Weber, Bernhard H. F.
A1  - Devilee, Peter
A1  - Tavtigian, Sean
A1  - Bader, Gary D.
A1  - Meindl, Alfons
A1  - Goldgar, David E.
A1  - Andrulis, Irene L.
A1  - Schmutzler, Rita K.
A1  - Easton, Douglas F.
A1  - Schmidt, Marjanka K.
A1  - Hahnen, Eric
A1  - Simard, Jacques
T1  - Uncovering the contribution of moderate-penetrance susceptibility genes to breast cancer by whole-exome sequencing and targeted enrichment sequencing of candidate genes in women of European ancestry
JF  - Cancers
N2  - Rare variants in at least 10 genes, including BRCA1, BRCA2, PALB2, ATM, and CHEK2, are associated with increased risk of breast cancer; however, these variants, in combination with common variants identified through genome-wide association studies, explain only a fraction of the familial aggregation of the disease. To identify further susceptibility genes, we performed a two-stage whole-exome sequencing study. In the discovery stage, samples from 1528 breast cancer cases enriched for breast cancer susceptibility and 3733 geographically matched unaffected controls were sequenced. Using five different filtering and gene prioritization strategies, 198 genes were selected for further validation. These genes, and a panel of 32 known or suspected breast cancer susceptibility genes, were assessed in a validation set of 6211 cases and 6019 controls for their association with risk of breast cancer overall, and by estrogen receptor (ER) disease subtypes, using gene burden tests applied to loss-of-function and rare missense variants. Twenty genes showed nominal evidence of association (p-value < 0.05) with either overall or subtype-specific breast cancer. Our study had the statistical power to detect susceptibility genes with effect sizes similar to ATM, CHEK2, and PALB2, however, it was underpowered to identify genes in which susceptibility variants are rarer or confer smaller effect sizes. Larger sample sizes would be required in order to identify such genes.
KW  - breast cancer
KW  - genetic susceptibility
KW  - whole-exome sequencing
KW  - moderate-penetrance genes
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-281768
SN  - 2072-6694
VL  - 14
IS  - 14
ER  - 
TY  - JOUR
A1  - Wiedenmann, J.
A1  - Bocquillon, E.
A1  - Deacon, R.S.
A1  - Hartinger, S.
A1  - Herrmann, O.
A1  - Klapwijk, T.M.
A1  - Maier, L.
A1  - Ames, C.
A1  - Brüne, C.
A1  - Gould, C.
A1  - Oiwa, A.
A1  - Ishibashi, K.
A1  - Tarucha, S.
A1  - Buhmann, H.
A1  - Molenkamp, L.W.
T1  - 4π-periodic Josephson supercurrent in HgTe-based topological Josephson junctions
JF  - Nature Communications
N2  - The Josephson effect describes the generic appearance of a supercurrent in a weak link between two superconductors. Its exact physical nature deeply influences the properties of the supercurrent. In recent years, considerable efforts have focused on the coupling of superconductors to the surface states of a three-dimensional topological insulator. In such a material, an unconventional induced p-wave superconductivity should occur, with a doublet of topologically protected gapless Andreev bound states, whose energies vary 4π-periodically with the superconducting phase difference across the junction. In this article, we report the observation of an anomalous response to rf irradiation in a Josephson junction made of a HgTe weak link. The response is understood as due to a 4π-periodic contribution to the supercurrent, and its amplitude is compatible with the expected contribution of a gapless Andreev doublet. Our work opens the way to more elaborate experiments to investigate the induced superconductivity in a three-dimensional insulator.
KW  - Josephson effect
KW  - supercurrent
KW  - superconductors
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-175353
VL  - 7
ER  -