Title: Josephson Detection of Multiband Effects in Superconductors
Abstract: The study of unconventional superconducting materials remains an active frontier of condensed matter physics. Exotic superconductivity, such as high T_C, topological, and heavy-fermion superconductors, often rely on phase sensitive measurements to determine the underlying pairing and/or the nature of novel excitations. In this talk I will detail the use of Josephson effect to detect novel properties of two multiband superconductors: NbSe_2 [1] and SnTe [2]. Focus be given to the modification of conventional Josephson effects due to the loss of time reversal symmetry found to exist in proximity-induced Josephson junction of SnTe nanowires [2]. Here we observe an interesting interplay between multiband effects and a ferroelectric transition. Each of these works open new routes to exploration of multiband effects in superconductors and have important implications for topological states in superconducting materials.
[1] S. Tran, J. Sell and J. R. Williams, “Dynamical Josephson Effects in NbSe2”, arXiv:1903.00453 (2019).
[2] C. J. Trimble et al., “Josephson Detection of Time Reversal Symmetry Broken Superconductivity in SnTe Nanowires”, arXiv:1907.04199 (2019).
Biosketch: James Williams is currently the Alford Ward Assistant Professor of Physics in the Physics Department at the University of Maryland working in quantum material devices. He is also a Fellow at the Joint Quantum Institute and a member of the Center for Nanophysics and Advanced Materials at the university. He performed his Ph. D. at Harvard University, working on creating nanoscale devices from of graphene. Prior to coming to Maryland, he was the Karl van Bibber Postdoctoral Fellow in the Physics Department at Stanford University where he worked on quantum transport in topological insulators and superconductors and complex oxide materials.
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2020-02-13T14:00:002020-02-13T15:00:00CM Seminar : Josephson Detection of Multiband Effects in SuperconductorsEvent Information:
Title: Josephson Detection of Multiband Effects in Superconductors
Abstract: The study of unconventional superconducting materials remains an active frontier of condensed matter physics. Exotic superconductivity, such as high T_C, topological, and heavy-fermion superconductors, often rely on phase sensitive measurements to determine the underlying pairing and/or the nature of novel excitations. In this talk I will detail the use of Josephson effect to detect novel properties of two multiband superconductors: NbSe_2 [1] and SnTe [2]. Focus be given to the modification of conventional Josephson effects due to the loss of time reversal symmetry found to exist in proximity-induced Josephson junction of SnTe nanowires [2]. Here we observe an interesting interplay between multiband effects and a ferroelectric transition. Each of these works open new routes to exploration of multiband effects in superconductors and have important implications for topological states in superconducting materials.
[1] S. Tran, J. Sell and J. R. Williams, “Dynamical Josephson Effects in NbSe2”, arXiv:1903.00453 (2019).
[2] C. J. Trimble et al., “Josephson Detection of Time Reversal Symmetry Broken Superconductivity in SnTe Nanowires”, arXiv:1907.04199 (2019).
Biosketch: James Williams is currently the Alford Ward Assistant Professor of Physics in the Physics Department at the University of Maryland working in quantum material devices. He is also a Fellow at the Joint Quantum Institute and a member of the Center for Nanophysics and Advanced Materials at the university. He performed his Ph. D. at Harvard University, working on creating nanoscale devices from of graphene. Prior to coming to Maryland, he was the Karl van Bibber Postdoctoral Fellow in the Physics Department at Stanford University where he worked on quantum transport in topological insulators and superconductors and complex oxide materials.Event Location:
Brimacombe 311