1
Return

Point-contact enhanced superconductivity in trigonal PtBi2: quest for the origin of ‘high-Tc’

delete2026-05-05
delete0
PRE
AI
O
O. E. Kvitnitskaya
L
Luminita Harnagea
G
Grigory Shipunov
S
S Aswartham
I
I Kovalchuk
V
V V Fisun
D
D. V. Efremov
B
B Büchner
Y
Yu. G. Naĭdyuk *
DOI:10.1088/1361-6668/ae61fbdelete
deleteOriginal
deleteOriginal request for help
deleteShare
deleteSave
Abstract

Abstract

En 中文
We studied enhanced superconductivity in point contacts (PCs) based on a type-I Weyl semimetal trigonal t-PtBi2 using both normal metal (Ag, Cu, Pt) and ferromagnetic (Fe, Co, Ni) tips by measuring the differential resistance dV/dI(V) curves. In most cases, the value of the superconducting critical temperature (Tc) ranges between 3 and 5 K, which is several times higher than the maximum bulk Tc. Notably, among the various PCs we examined, a few achieved Tc values as high as 8 K, including those with both normal and ferromagnetic tips. Additionally, the critical magnetic field is also highly enhanced in these PCs and reaches up to several Tesla. The common reason for the Tc increase may be related to pressure/strain caused during the PC’s formation. It is worth noting that a greater increase in Tc is observed in PCs formed at the edge of the sample flake, compared to those formed on the plane of the platelet. The results also reveal that the enhancement of Tc in PCs based on t-PtBi2 is compatible with ferromagnetic tips, which may suggest a potentially complex nature of enhanced superconductivity. Our findings suggest that t-PtBi2 is a promising candidate for realizing topological superconductivity at more accessible temperatures.
Keywords:
superconductivity
point contacts
t-PtBi2
critical temperature
ferromagnetic tips

Journal

Superconductor Science and Technology cover
Superconductor Science and Technology
IF:
4.2
Papers:
8.3K
Citations:
1.2W

Organization

K
Kyiv Academic University
Scholars:
22
Papers: 15
Citations: 43
L
Leibniz Institute for Solid State and Materials Research
Scholars:
114
Papers: 54
Citations: 3.9K
Cited Papers

Cited Papers

Citing Papers

Citing Papers