Berlin 2018 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

TT: Fachverband Tiefe Temperaturen

TT 9: Quantum Dots, Quantum Wires, Point Contacts

TT 9.6: Talk

Monday, March 12, 2018, 11:00–11:15, HFT-FT 101

Temperature effects in superconducting quantum dots — •Vladislav Pokorný¹ and Martin Žonda² — ¹Institute of Physics, Na Slovance 2, 18221 Prague, Czech Republic — ²Faculty of Mathematics and Physics, Charles University, Ke Karlovu 5, 12116 Prague, Czech Republic

We study the temperature effects in a system consisting of a single-level quantum dot with local Coulomb interaction attached to two superconducting leads and optionally a third, metallic lead. The system is described by the single-impurity Anderson model coupled to BCS superconducting baths and solved using the continuous-time, hybridization-expansion (CT-HYB) quantum Monte Carlo as well as the numerical renormalization group (NRG). We study the behavior of the subgap (Andreev-Shiba) states, the Josephson current and the fate of the zero-pi (singlet-doublet) quantum phase transition. We also show the limits of usability of the stochastic optimization method for obtaining the spectral functions from the imaginary-time CT-HYB results.