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Title: Concurrence of superconductivity and structure transition in Weyl semimetal TaP under pressure

Abstract

Weyl semimetal defines a material with three-dimensional Dirac cones, which appear in pair due to the breaking of spatial inversion or time reversal symmetry. Superconductivity is the state of quantum condensation of paired electrons. Turning a Weyl semimetal into superconducting state is very important in having some unprecedented discoveries. In this work, by doing resistive measurements on a recently recognized Weyl semimetal TaP under pressures up to about 100 GPa, we show the concurrence of superconductivity and a structure transition at about 70 GPa. It is found that the superconductivity becomes more pronounced when decreasing pressure and retains when the pressure is completely released. High-pressure x-ray diffraction measurements also confirm the structure phase transition from I41md to P-6m2 at about 70 GPa. More importantly, ab-initial calculations reveal that the P-6m2 phase is a new Weyl semimetal phase and has only one set of Weyl points at the same energy level. Our discovery of superconductivity in TaP by high pressure will stimulate investigations on superconductivity and Majorana fermions in Weyl semimetals.

Authors:
; ; ; ; ORCiD logo; ; ORCiD logo; ; ; ; ; ; ; ORCiD logo; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
DOE - BASIC ENERGY SCIENCESNSFDOE-NNSAFOREIGN
OSTI Identifier:
1418051
Resource Type:
Journal Article
Resource Relation:
Journal Name: npj Quantum Materials; Journal Volume: 2; Journal Issue: 1
Country of Publication:
United States
Language:
ENGLISH
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY

Citation Formats

Li, Yufeng, Zhou, Yonghui, Guo, Zhaopeng, Han, Fei, Chen, Xuliang, Lu, Pengchao, Wang, Xuefei, An, Chao, Zhou, Ying, Xing, Jie, Du, Guan, Zhu, Xiyu, Yang, Huan, Sun, Jian, Yang, Zhaorong, Yang, Wenge, Mao, Ho-Kwang, Zhang, Yuheng, and Wen, Hai-Hu. Concurrence of superconductivity and structure transition in Weyl semimetal TaP under pressure. United States: N. p., 2017. Web. doi:10.1038/s41535-017-0066-z.
Li, Yufeng, Zhou, Yonghui, Guo, Zhaopeng, Han, Fei, Chen, Xuliang, Lu, Pengchao, Wang, Xuefei, An, Chao, Zhou, Ying, Xing, Jie, Du, Guan, Zhu, Xiyu, Yang, Huan, Sun, Jian, Yang, Zhaorong, Yang, Wenge, Mao, Ho-Kwang, Zhang, Yuheng, & Wen, Hai-Hu. Concurrence of superconductivity and structure transition in Weyl semimetal TaP under pressure. United States. doi:10.1038/s41535-017-0066-z.
Li, Yufeng, Zhou, Yonghui, Guo, Zhaopeng, Han, Fei, Chen, Xuliang, Lu, Pengchao, Wang, Xuefei, An, Chao, Zhou, Ying, Xing, Jie, Du, Guan, Zhu, Xiyu, Yang, Huan, Sun, Jian, Yang, Zhaorong, Yang, Wenge, Mao, Ho-Kwang, Zhang, Yuheng, and Wen, Hai-Hu. Fri . "Concurrence of superconductivity and structure transition in Weyl semimetal TaP under pressure". United States. doi:10.1038/s41535-017-0066-z.
@article{osti_1418051,
title = {Concurrence of superconductivity and structure transition in Weyl semimetal TaP under pressure},
author = {Li, Yufeng and Zhou, Yonghui and Guo, Zhaopeng and Han, Fei and Chen, Xuliang and Lu, Pengchao and Wang, Xuefei and An, Chao and Zhou, Ying and Xing, Jie and Du, Guan and Zhu, Xiyu and Yang, Huan and Sun, Jian and Yang, Zhaorong and Yang, Wenge and Mao, Ho-Kwang and Zhang, Yuheng and Wen, Hai-Hu},
abstractNote = {Weyl semimetal defines a material with three-dimensional Dirac cones, which appear in pair due to the breaking of spatial inversion or time reversal symmetry. Superconductivity is the state of quantum condensation of paired electrons. Turning a Weyl semimetal into superconducting state is very important in having some unprecedented discoveries. In this work, by doing resistive measurements on a recently recognized Weyl semimetal TaP under pressures up to about 100 GPa, we show the concurrence of superconductivity and a structure transition at about 70 GPa. It is found that the superconductivity becomes more pronounced when decreasing pressure and retains when the pressure is completely released. High-pressure x-ray diffraction measurements also confirm the structure phase transition from I41md to P-6m2 at about 70 GPa. More importantly, ab-initial calculations reveal that the P-6m2 phase is a new Weyl semimetal phase and has only one set of Weyl points at the same energy level. Our discovery of superconductivity in TaP by high pressure will stimulate investigations on superconductivity and Majorana fermions in Weyl semimetals.},
doi = {10.1038/s41535-017-0066-z},
journal = {npj Quantum Materials},
number = 1,
volume = 2,
place = {United States},
year = {Fri Dec 01 00:00:00 EST 2017},
month = {Fri Dec 01 00:00:00 EST 2017}
}
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