Surface superconductivity in the topological Weyl semimetal t-PtBi${}_2$

Abstract

The advancement of quantum computation is eager on generating fault tolerant qubits, and topological superconductivity is a very promising concept for reaching this goal. Early experimental achievements study hybrid systems as well as doped intrinsic topological or superconducting materials presenting the phenomena at very low temperatures. However, higher critical temperatures are indispensable for technological exploitation. Promising very recent angle-resolved photoemission spectroscopy results reveal that superconductivity of the type-I Weyl semimetal trigonal PtBi${}_2$ (t-PtBi${}_2$) is located at the Fermi arcs surface states which renders t-PtBi${}_2$ a candidate for intrinsic topological superconductivity. Here we show, using scanning tunnelling microscopy and spectroscopy (STM/STS) that t-PtBi${}_2$ presents surface superconductivity at elevated temperatures (5 K). The gap magnitude is elusive: it is spatially inhomogeneous and spans from 0 to 20 meV. In particular, the large gap value and the shape of the quasiparticle excitation spectrum resemble the phenomenology of high-Tc superconductors. To our knowledge, this is the largest superconducting gap so far measured in a topological material. Moreover, we show that the superconducting state at 5 K persists up to 12 T magnetic field. Thus, we show that t-PtBi2 is a prime candidate for intrinsic topological superconductivity at technologically relevant temperatures, fields and gap magnitudes.

Revised Version

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Cited by in corpus (15)

• Self-consistent surface superconductivity in time-reversal symmetric Weyl semimetals
• Phonon-mediated intrinsic topological superconductivity in Fermi arcs
• Topological nodal $i$-wave superconductivity in PtBi${}_2$
• Superconducting density of states of PtPb4
• Investigation on high-order planar Hall effect in trigonal PtBi${}_2$
• Ginzburg-Landau theory for unconventional surface superconductivity in PtBi${}_2$
• Dissipationless transport signature of topological nodal lines
• Interplay between inversion and translation symmetries in trigonal PtBi${}_2$
• Atomic Visualization of Bulk and Surface Superconductivity in Weyl Semimetal γ-PtBi2
• Direct observation of the surface superconducting gap in the topological superconductor candidate β-PdBi2
• Higher-order topological superconductivity in type-II time-reversal-symmetric Weyl semimetals with a hybrid pairing
• Observation of two-level critical-state in a van-der-Waals superconductor Pt(Bi${}_{1-x}$Se${}_x$)${}_2$
• Conventional superconductivity in single-crystalline BiPt
• Mechanism for Nodal Topological Superconductivity on PtBi${}_2$ Surface
• Emergence of Double-Dome Superconductivity in the Pressurized Dirac Semimetal BaMg2Bi2