IFISC Seminar on Thursday Jun 02, 2022 at 14:30 Place: IFISC Seminar Room Title: Yu-Shiba-Rusinov subgap excitations in hybrid superconductor/semiconductor nanowires containing quantum dots Speaker: Ramón Aguado , Instituto de Ciencia de Materiales de Madrid, CSIC Abstract: <p>The physics of a quantum impurity in a superconductor is governed by the fermionic parity and spin of the two possible ground states, doublet or singlet, and their corresponding Yu-Shiba-Rusinov subgap excitations. After an introduction about their role in hybrid superconductor/semiconductor nanowires containing quantum dots [1], I will focus on semiconducting nanowires fully wrapped by a superconductor where an external magnetic flux gives rise to&nbsp;new regimes hitherto unexplored&nbsp;[2].</p> <p>In the second part, I will discuss the physics of a superconducting qubit whose Josephson energy is governed by a fully tunable quantum dot. Specifically, a&nbsp;circuit&nbsp;QED setup&nbsp;allows to probe both its ground state and&nbsp;quasiparticle dynamics, resulting in,&nbsp;arguably, the most in-depth experimental study of a superconducting quantum impurity to date [3]. &nbsp;These results hold promise for&nbsp;realizing&nbsp;Andreev qubits with long parity lifetimes.&nbsp;</p> <p>[1] &nbsp;Lee et al Phys. Rev. Lett. 109, 186802 (2012); Žitko et al, Phys. Rev. B 91, 045441 (2015); &nbsp;Lee et al, Nature Nanotech., 9, 79-84 (2014).</p> <p>[2] Valentini et al, Science 373, 82-88 (2021); Escribano et al, Phys.&nbsp;Rev.&nbsp;B 105, 045418 (2022).</p> <p>[3] Bargerbos et al arXiv:2202.12754. PRX Quantum, in press.</p> <p><span style="color:#c0392b"><strong>Note the unusual day of the week.</strong></span></p> <p><span style="color:null">The seminar is presential with parallel zoom stream:&nbsp;</span>https://zoom.us/j/98286706234?pwd=bm1JUFVYcTJkaVl1VU55L0FiWDRIUT09</p>; Url event:https://ifisc.uib-csic.es/en/events/seminars/yu-shiba-rusinov-subgap-excitat...