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Title: Pressure-induced superconductivity in a novel germanium allotrope
High-pressure studies on elements play an essential role in superconductivity research, with implications for both fundamental science and applications. Here we report the experimental discovery of surprisingly low pressure driving a novel germanium allotrope into a superconducting state in comparison to that for α-Ge. Raman measurements revealed structural phase transitions and possible electronic topological transitions under pressure up to 58 GPa. Based on pressure-dependent resistivity measurements, superconductivity was induced above 2 GPa and the maximum Tc of 6.8 K was observed under 4.6 GPa. Interestingly, a superconductivity enhancement was discovered during decompression, indicating the possibility of maintaining pressure-induced superconductivity at ambient pressure with better superconducting performance. Density functional theory analysis further suggested that the electronic structure of Ge (oP32) is sensitive to its detailed geometry and revealed that disorder in the β-tin structure leads to a higher Tc in comparison to the perfect β-tin Ge.  more » « less
Award ID(s):
2104881
PAR ID:
10488389
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ;
Corporate Creator(s):
Editor(s):
-
Publisher / Repository:
DOE Pages
Date Published:
Journal Name:
Materials Today Physics
Edition / Version:
1
Volume:
41
Issue:
C
ISSN:
2542-5293
Page Range / eLocation ID:
101338
Subject(s) / Keyword(s):
Superconductivity Element superconductor High pressure Phase transition Allotope
Format(s):
Medium: X Size: 5.8M Other: pdf
Size(s):
5.8M
Sponsoring Org:
National Science Foundation
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