Anisotropic electron and lattice dynamics in excitonic insulator Ta2NiSe5

doi:10.1063/5.0086701

	Anisotropic electron and lattice dynamics in excitonic insulator Ta2NiSe5
	Chu, Lingqiao 1,3; Zhang, Kai 3; Yang, Jin 3; Jiang, Huachao 3; Wang, Zhenyou 2; Su, Fuhai 3
刊名	AIP ADVANCES
	2022-05-01
卷号	12
DOI	10.1063/5.0086701
通讯作者	Su, Fuhai(fhsu@issp.ac.cn)
英文摘要	We employ polarization-resolved femtosecond optical pump-probe spectroscopy to investigate the nonequilibrium photocarrier dynamics in excitonic insulator Ta2NiSe5. The electronic dynamics, including hot carrier cooling, exciton formation, and recombination in the timescale ranging from subpicoseconds to a few tens of picoseconds, have been established from the transient reflectivity spectra, showing strong in-plane anisotropy with respect to the probe polarization. Such anisotropic photocarrier dynamics possibly arise from the crystalline orientation dependence of the excitonic polarizability. Furthermore, we find that the amplitude of coherent phonons with a frequency of 1 THz is subject to the probe polarization, whereas it is not sensitive to the pump polarization. This substantiates that the displacive excitation of coherent phonons plays a decisive role in lattice dynamics. In addition, we find that the photo-induced dielectric screening tends to suppress the amplitude of coherent phonons with increasing pump fluence, manifesting a remarkable polarization dependence. Our work provides valuable insights into the excitonic dynamics and the origin of coherent phonon generation and also may contribute to the development of polarization-sensitive photoelectric devices based on Ta2NiSe5. (C)& nbsp;2022 Author(s).
资助项目	National Natural Science Foundation of China[11774354] ; National Natural Science Foundation of China[12004387] ; National Natural Science Foundation of China[12174398] ; National Natural Science Foundation of China[51727806] ; Science Challenge Project[TZ2016001] ; CAS Innovation Grant[CXJJ-19-B08]
WOS关键词	PHASE
WOS研究方向	Science & Technology - Other Topics ; Materials Science ; Physics
语种	英语
出版者	AIP Publishing
WOS记录号	WOS:000797231900003
资助机构	National Natural Science Foundation of China ; Science Challenge Project ; CAS Innovation Grant
内容类型	期刊论文
源URL	[http://ir.hfcas.ac.cn:8080/handle/334002/130921]
专题	中国科学院合肥物质科学研究院
通讯作者	Su, Fuhai
作者单位	1.Anhui Univ, Inst Phys Sci & Informat Technol, Hefei 230601, Peoples R China 2.Chinese Acad Sci, GBA Branch Aerosp Informat Res Inst, Guangzhou 510700, Peoples R China 3.Chinese Acad Sci, Inst Solid State Phys, HFIPS, Key Lab Mat Phys, Hefei 230031, Peoples R China
推荐引用方式 GB/T 7714	Chu, Lingqiao,Zhang, Kai,Yang, Jin,et al. Anisotropic electron and lattice dynamics in excitonic insulator Ta2NiSe5[J]. AIP ADVANCES,2022,12.
APA	Chu, Lingqiao,Zhang, Kai,Yang, Jin,Jiang, Huachao,Wang, Zhenyou,&Su, Fuhai.(2022).Anisotropic electron and lattice dynamics in excitonic insulator Ta2NiSe5.AIP ADVANCES,12.
MLA	Chu, Lingqiao,et al."Anisotropic electron and lattice dynamics in excitonic insulator Ta2NiSe5".AIP ADVANCES 12(2022).