Electronic structure and superconductivity of the non-centrosymmetric Sn4As3

DOI: 10.1088/1367-2630/ab890a

Authors: Carolina De Almeida Marques (University of St Andrews) , Matthew James Neat (University of St Andrews) , Chi Ming Yim (University of St Andrews) , Matthew D. Watson (University of St Andrews) , Luke Charles Rhodes (University of St Andrews) , Christoph Heil (Graz University of Technology Institute of Theoretical and Computational Physics) , Kirill Pervakov (P N Lebedev Physical Institute, Russian Academy of Sciences) , Vladimir Vlasenko (P N Lebedev Physical Institute, Russian Academy of Sciences) , Vladimir Pudalov (P N Lebedev Physical Institute, Russian Academy of Sciences) , Andrei Muratov (P N Lebedev Physical Institute, Russian Academy of Sciences) , Timur Kim (Diamond Light Source) , Peter Wahl (University of St Andrews)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: New Journal Of Physics

State: Published (Approved)
Published: April 2020
Diamond Proposal Number(s): 15663

Abstract: In a superconductor that lacks inversion symmetry, the spatial part of the Cooper pair wave function has a reduced symmetry, allowing for the mixing of spin-singlet and spin-triplet Cooper pairing channels and thus providing a pathway to a non-trivial superconducting state. Materials with a non-centrosymmetric crystal structure and with strong spin-orbit coupling are a platform to realize these possibilities. Here, we report the synthesis and characterisation of high quality crystals of Sn4As3, with non-centrosymmetric unit cell (R3m). We have characterised the normal and superconducting state using a range of methods. Angle-resolved photoemission spectroscopy shows a multiband Fermi surface and the presence of two surface states, confirmed by Density-functional theory calculations. Specific heat measurements reveal a superconducting critical temperature of T c~ 1.14 K and an upper critical magnetic field of H cgsim 7 mT, which are both confirmed by ultra-low temperature scanning tunneling microscopy and spectroscopy. Scanning tunneling spectroscopy shows a fully formed superconducting gap, consistent with conventional s-wave superconductivity.

Subject Areas: Physics, Materials


Instruments: I05-ARPES

Added On: 01/05/2020 09:14

Documents:
de+Almeida+Marques+et+al_2020_New_J._Phys._10.1088_1367-2630_ab890a.pdf

Discipline Tags:

Superconductors Quantum Materials Physics Hard condensed matter - structures Materials Science

Technical Tags:

Spectroscopy Angle Resolved Photoemission Spectroscopy (ARPES)