James T. Farmer

Sep 22, 2023 | link.aps.org | Bassel Heiba Elfeky |William Strickland |Jaewoo Lee |James T. Farmer

Popular Summary Standard Josephson tunnel junctions, formed by two superconducting layers sandwiching a nm-thick insulating barrier, conduct current through the tunneling of Cooper pairs. Current in a Josephson junction based on indium arsenide, however, is carried by coherent reflections of normal electrons and holes at the two interfaces forming Andreev bound states.

Apr 27, 2023 | link.aps.org | James T. Farmer |Azarin Zarassi |Sadman Shanto |Darian Hartsell

Abstract We report continuous measurements of quasiparticles trapping and clearing from Andreev bound states in aluminum nanobridge Josephson junctions integrated into a superconducting-qubit-like device. We find that trapping is well modeled by independent spontaneous emission events. Above 80 mK the clearing process is well described by the absorption of thermal phonons, but other temperature-independent mechanisms dominate at low temperature.

Apr 26, 2023 | link.aps.org | James T. Farmer