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PRODID:UW-Madison-Physics-Events
BEGIN:VEVENT
SEQUENCE:1
UID:UW-Physics-Event-8792
DTSTART:20241114T160000Z
DTEND:20241115T000000Z
DTSTAMP:20260413T170650Z
LAST-MODIFIED:20241108T213136Z
LOCATION:5310 Chamberlin
SUMMARY:Extrinsic and intrinsic superconducting diode effects\, R. G. 
 Herb Condensed Matter Seminar\, Jukka Vayrynen\, Purdue University
DESCRIPTION:
\nThe critical current of a superconducting wire can be n
 on-reciprocal\, i.e.\, dependent on current direction\, when inversion
  and time-reversal symmetry are broken. This so-called superconducting
  diode effect has gained renewed attention in recent years\, due to th
 e possibility that the effect may arise from the interplay of spin-orb
 it coupling and Zeeman effect in a uniform superconductor. I will disc
 uss the superconducting diode effect originating from two different me
 chanisms\, studied in recent preprints [1-2]. The first one is an extr
 insic one arising from the geometry of the setup rather than intrinsic
  properties. It is however relevant for uniform superconducting hetero
 structures due to the formation of interfacial diamagnetic currents an
 d Josephson vortices [1]. In the second part of the talk\, I will disc
 uss an intrinsic mechanism that is relevant for generic quasi-one-dime
 nsional superconducting system where the critical current is determine
 d by Cooper pair depairing. By introducing a minimal model\, we find t
 he key ingredients to obtain intrinsic superconducting diode effect. T
 he model can be microscopically derived as a low-energy limit of a Ras
 hba spin-orbit coupled superconductor in a Zeeman field [2] or of an e
 dge state of a two-dimensional topological insulator [3]. The results 
 quantify how system parameters such as spin-orbit coupling and quantum
  confinement affect the strength of the diode effect and provide a com
 plementary description to previous Ginzburg-Landau theories of the eff
 ect.
\n
\n[1] Diamagnetic mechanism of critical current non-reciprocit
 y in multilayered superconductors\, Sundaresh\, Vayrynen\, Lyanda-Gell
 er\, Rokhinson\, arXiv:2207.03633.
\n[2] Superconducting diode effect 
 in quasi-one-dimensional systems\, de Picoli\, Blood\, Lyanda-Geller\,
  Vayrynen\, arXiv:2302.04277
\n[3] Superconducting Diode Effect in Two
 -dimensional Topological Insulator Edges and Josephson Junctions\, Hua
 ng\, de Picoli\, Vayrynen\, arXiv:2404.14566
\n
URL:https://www.physics.wisc.edu/events/?id=8792
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