Electron-phonon coupling and superconductivity in the doped topological crystalline insulator (Pb0.5Sn0.5)(1-x)InxTe

doi:10.1103/PhysRevB.102.104511

	Electron-phonon coupling and superconductivity in the doped topological crystalline insulator (Pb0.5Sn0.5)(1-x)InxTe
	Sapkota, A.1; Li, Y.1; Winn, B. L.2; Podlesnyak, A.2; Xu, Guangyong 3; Xu, Zhijun 3,4; Ran, Kejing5 ; Chen, Tong 6,7; Sun, Jian 6,7,8; Wen, Jinsheng 6,7,8; Wu, Lihua 9; Yang, Jihui 9; Li, Qiang 1; Gu, G. D.1; Tranquada, J. M.1
	2020-09-23
发表期刊	PHYSICAL REVIEW B (IF:3.2[JCR-2023],3.3[5-Year])
ISSN	2469-9950
卷号	102 期号:10
DOI	10.1103/PhysRevB.102.104511
摘要	We present a neutron-scattering study of phonons in single crystals of (Pb0.5Sn0.5)(1-x)InxTe with x = 0 (metallic, but nonsuperconducting) and x = 0.2 (nonmetallic normal state, but superconducting). We map the phonon dispersions (more completely for x = 0) and find general consistency with theoretical calculations, except for the transverse and longitudinal optical (LO) modes at the Brillouin-zone center. At low temperature, both modes are strongly damped but sit at a finite energy (approximate to 4meV in both samples), shifting to higher energy at room temperature. These modes are soft due to a proximate structural instability driven by the sensitivity of Pb-Te and Sn-Te p-orbital hybridization to off-center displacements of the metal atoms. The impact of the soft optical modes on the low-energy acoustic modes is inferred from the low thermal conductivity, especially at low temperature. Given that the strongest electron-phonon coupling is predicted for the LO mode, which should be similar for both studied compositions, it is intriguing that only the In-doped crystal is superconducting. In addition, we observe elastic diffuse (Huang) scattering that is qualitatively explained by the difference in Pb-Te and Sn-Te bond lengths within the lattice of randomly distributed Pb and Sn sites. We also confirm the presence of anomalous diffuse low-energy atomic vibrations that we speculatively attribute to local fluctuations of individual Pb atoms between off-center sites.
收录类别	SCI ; SCIE ; EI
语种	英语
资助项目	Office of Basic Energy Sciences, Materials Sciences and Engineering Division, U.S. Department of Energy (DOE)[DE-SC0012704] ; National Natural Science Foundation of China[11822405][11674157] ; Natural Science Foundation of Jiangsu Province[BK20180006] ; National Science Foundation[1915933]
WOS研究方向	Materials Science ; Physics
WOS类目	Materials Science, Multidisciplinary ; Physics, Applied ; Physics, Condensed Matter
WOS记录号	WOS:000571989400010
出版者	AMER PHYSICAL SOC
引用统计	正在获取...
文献类型	期刊论文
条目标识符	https://kms.shanghaitech.edu.cn/handle/2MSLDSTB/123538
专题	物质科学与技术学院_公共科研平台_拓扑物理实验室
通讯作者	Sapkota, A.
作者单位	1.Brookhaven Natl Lab, Condensed Matter Phys & Mat Sci Div, Upton, NY 11973 USA; 2.Oak Ridge Natl Lab, Neutron Scattering Div, Oak Ridge, TN 37831 USA; 3.NIST, Ctr Neutron Res, Gaithersburg, MD 20899 USA; 4.Univ Maryland, Dept Mat Sci & Engn, College Pk, MD 20742 USA; 5.ShanghaiTech Univ, Sch Phys Sci & Technol, Shanghai 201210, Peoples R China; 6.Nanjing Univ, Natl Lab Solid State Microstruct, Nanjing 210093, Peoples R China; 7.Nanjing Univ, Dept Phys, Nanjing 210093, Peoples R China; 8.Nanjing Univ, Collaborat Innovat Ctr Adv Microstruct, Nanjing 210093, Peoples R China; 9.Univ Washington, Mat Sci & Engn Dept, Seattle, WA 98195 USA
推荐引用方式 GB/T 7714	Sapkota, A.,Li, Y.,Winn, B. L.,et al. Electron-phonon coupling and superconductivity in the doped topological crystalline insulator (Pb0.5Sn0.5)(1-x)InxTe[J]. PHYSICAL REVIEW B,2020,102(10).
APA	Sapkota, A..,Li, Y..,Winn, B. L..,Podlesnyak, A..,Xu, Guangyong.,...&Tranquada, J. M..(2020).Electron-phonon coupling and superconductivity in the doped topological crystalline insulator (Pb0.5Sn0.5)(1-x)InxTe.PHYSICAL REVIEW B,102(10).
MLA	Sapkota, A.,et al."Electron-phonon coupling and superconductivity in the doped topological crystalline insulator (Pb0.5Sn0.5)(1-x)InxTe".PHYSICAL REVIEW B 102.10(2020).