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Topology driven magnetic memory of OsB2 surface states

Nikhlesh S. Mehta1, Bikash Patra2, Mona Garg1, Ghulam Mohmad1, Pooja Bhardwaj3, Savita Chaudhary1, Jaskaran Singh1, Yogesh Singh1, Bahadur Singh2 et al.

Goutam Sheet1,*

  • *Contact author: goutam@iisermohali.ac.in
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Phys. Rev. B 113, 134529 – Published 30 April, 2026

DOI: https://doi.org/10.1103/l3bd-c4my

Abstract

The development of superconducting data storage devices is one of the coveted goals for next-generation low-power electronics, and interaction between superconducting and nontrivial topological states can potentially be useful to achieve this goal. Here we show that the superconducting diboride OsB2 hosts an anisotropic superconducting order parameter along with topological surface states which are spin polarized. Through the measurement of Andreev reflection on the surface of OsB2 we find that the superconducting order parameter senses the spin polarization of the topological surface states. As a consequence, the order parameter retains the memory of the exposure to a magnetic field, leading to a magnetic-field-dependent hysteresis effect. Thus we present nanoscale metallic junctions made on the surface of OsB2 as energy-efficient superconducting memory devices.

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Phys. Rev. B 113, 134529– Published 30 April, 2026
  • Received 9 August 2025
  • Revised 19 March 2026
  • Accepted 6 April 2026
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