288th RQC Seminar

• 講演者

  Prof. MATOS-ABIAGUE Alex
  ( Department of Physics and Astronomy, Wayne State University, Detroit MI, USA )

• 日程

  2026年6月25日(木), 13:00 - 14:00(1:00 p.m.-2:00 p.m.)

• 開催場所

  オンサイト（ 424-426 Seminar Room, 4F, Main Research Building, Wako Campus / 和光地区 研究本館4階 特別会議室 (424-426) (C01))

• 講演タイトル

  Magneto-Current–Phase Relations in Planar Josephson Junctions: Probing Topological Superconductivity and Anisotropic Josephson Diode Effects

• お問合せ

  peter.stano[at]riken.jp

講演概要
We present a theoretical study of topological superconductivity in proximitized planar Josephson junctions (JJs), demonstrating how structural and magnetic mirror symmetries enable distinct topological classes hosting multiple Majorana states whose localization character can be tuned from end-like to edge-like by varying the superconducting phase difference across the junction. We further show that the magneto–current–phase relation (magneto-CPR) provides direct signatures of topological gap closings, enables reconstruction of the topological phase diagram, and allows experimental estimation of key parameters such as the Rashba spin–orbit coupling (SOC) strength. The magneto-CPR also reveals the behavior of the Josephson diode effect (JDE) and its dependence on SOC, Zeeman field, and junction transparency. A symmetry analysis identifies magnetic-field and crystallographic orientations for which the JDE is suppressed, offering experimentally testable signatures of the interplay between Rashba and Dresselhaus SOCs, and Zeeman coupling. In addition, numerical simulations show that electrostatic gating can induce polarity reversals of the JDE in the low-field regime even in the presence of only Rashba SOC, consistent with recent experiments, and predict further reversals for specific field orientations, junction geometries, and SOC ratios. These results establish magneto-CPR measurements as a versatile probe of topological superconductivity and nonreciprocal transport in semiconductor-based planar JJs.