Quasiparticle dynamics and electron-phonon coupling in Weyl semimetal TaAs

被引：27

作者：

Wu, Qiong ^{[1
,2
]}

Sun, Fei ^{[1
,2
]}

Zhang, Qianyu ^{[1
]}

Zhao, L. X. ^{[1
]}

Chen, G-F ^{[1
,2
,3
]}

Zhao, Jimin ^{[1
,2
,3
]}

机构：

[1] Chinese Acad Sci, Inst Phys, Beijing Natl Lab Condensed Matter Phys, Beijing 100190, Peoples R China

[2] Univ Chinese Acad Sci, Sch Phys Sci, Beijing 100049, Peoples R China

[3] Songshan Lake Mat Lab, Dongguan 523808, Guangdong, Peoples R China

来源：

PHYSICAL REVIEW MATERIALS | 2020年 / 4卷 / 06期

基金：

北京市自然科学基金; 中国国家自然科学基金;

关键词：

TRANSITION-TEMPERATURE; OPTICAL-DETECTION; TIME; RELAXATION;

D O I：

10.1103/PhysRevMaterials.4.064201

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We report ultrafast quasiparticle (QP) dynamics of TaAs, from which we obtain its electron-phonon coupling (EPC) strength. Two relaxation components with lifetimes tau(f)(ast) = 0.48 ps and tau(slow) = 250 ps are observed, each of which exhibits a smooth temperature dependence. Furthermore, we carry out a fluence-dependence investigation, based on which the quantitative analysis of the fast relaxation component yields a constant EPC strength lambda with lambda <Omega(3)>/<Omega >(2) approximate to 5.2 ps(-1). In addition, our rotational polarization angle experiment demonstrates that the QP ultrafast dynamics is nearly isotropic under the given excitation geometry. Our investigation of the EPC strength accounts for the so far relatively rarely explored medium fluence regime, which can be generalized to various types of quantum materials.

引用

页数：6

共 48 条

[1] Long-lived optical phonons in ZnO studied with impulsive stimulated Raman scattering -: art. no. 205211 [J].