Hybridization-mediated quasiparticle and phonon dynamics in single crystal cerium films  

作　　者：Yunhe Pei Yi Wu Kai Hu Zhengxing Wei YiFeng Yang Yang Liu Jingbo Qi 

机构地区：[1]State Key Laboratory of Electronic Thin Films and Integrated Devices,University of Electronic Science and Technology of China,Chengdu 611731,China [2]Center for Correlated Matter and Department of Physics,Zhejiang University,Hangzhou 310058,China [3]Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China [4]University of Chinese Academy of Sciences,Beijing 100049,China [5]Songshan Lake Materials Laboratory,Dongguan 523808,China [6]Collaborative Innovation Center of Advanced Microstructures,Nanjing University,Nanjing 210093,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2024年第4期146-153,共8页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the National Key Research and Development Program of China(Grant Nos.2022YFA1403000,and 2022YFA1402200);the National Natural Science Foundation of China(Grant Nos.92365102,11974070,11734006,11925408,11921004,12004067,62027807,and 12174331);the Frontier Science Project of Dongguan(Grant No.2019622101004)。

摘　　要：We report the ultrafast optical pump-probe spectroscopy measurements on the single-crystal cerium films.Our experimental results of temperature-dependent quasiparticle dynamics reveal development of the hybridization between localized f moments and conduction electrons,i.e.,evolving from fluctuating hybridization to collective hybridization.Exotic phonon renormalization is discovered to appear at the emerging temperature(T^(+))of fluctuating hybridization apart from its known presence at the coherent temperature(T^(*)),and can hardly be explained by the mean-field theory.The quasiparticle relaxation at high temperatures indicates coexistence of nonthermal electron-electron scattering and inelastic Kondo scattering,while its behavior at low temperatures suggests onset ofαphase in theγ-phase dominated film.We also extract the indirect gap below T^(*),representing the appearance of collective hybridization.Our findings provide novel information about the hybridization and phase evolution in the heavy fermion systems.

关 键 词：CERIUM quasiparticle dynamics HYBRIDIZATION phonon renormalization 

分 类 号：O469[理学—凝聚态物理]