Transition from three- to two-dimensional Ising superconductivity in few-layer NbSe2 by proximity effect from van der Waals heterostacking

Prakiran Baidya; Divya Sahani; Hemanta Kumar Kundu; Simrandeep Kaur; Priya Tiwari; Vivas Bagwe; John Jesudasan; Awadhesh Narayan; Pratap Raychaudhuri; Aveek Bid

doi:10.1103/physrevb.104.174510

arXiv · 2111.06681

Transition from three- to two-dimensional Ising superconductivity in few-layer NbSe2 by proximity effect from van der Waals heterostacking

Prakiran Baidya·Divya Sahani·Hemanta Kumar Kundu·Simrandeep Kaur·Priya Tiwari·Vivas Bagwe·John Jesudasan·Awadhesh Narayan·Pratap Raychaudhuri·Aveek Bid

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Abstract

We report the experimental observation of Ising superconductivity in 3-dimensional NbSe2 stacked with single-layer MoS2. The angular dependence of the upper critical magnetic field and the temperature dependence of the upper parallel critical field confirm the appearance of two-dimensional Ising superconductivity in the 3-dimensional NbSe2 with single-layer MoS2 overlay. We show that the superconducting phase has strong Ising spin-orbit correlations which make the holes spin non-degenerate. Our observation of Ising superconductivity in heterostructures of few-layer NbSe2 of thickness ~ 15 nm with single-layer MoS2 raises the interesting prospect of observing topological chiral superconductors with nontrivial Chern numbers in a momentum-space spin-split fermionic system.

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Prakiran Baidya, Divya Sahani, Hemanta Kumar Kundu, Simrandeep Kaur, Priya Tiwari, Vivas Bagwe, John Jesudasan, Awadhesh Narayan, Pratap Raychaudhuri, Aveek Bid. 2021-11-12. Transition from three- to two-dimensional Ising superconductivity in few-layer NbSe2 by proximity effect from van der Waals heterostacking. https://doi.org/10.1103/physrevb.104.174510

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