Selective substitution induced anomalous phonon stiffening within quasi-one-dimensional P–P chains in SiP2  

作　　者：Xueting Dai Feng Qin Caiyu Qiu Ling Zhou Junwei Huang Fanghua Cheng Xiangyu Bi Caorong Zhang Zeya Li Ming Tang Shengqiang Wu Xiaoxu Zhao Yangfan Lu Huiyang Gou Hongtao Yuan 

机构地区：[1]National Laboratory of Solid State Microstructures,Jiangsu Key Laboratory of Artificial Functional Materials,College of Engineering and Applied Sciences,and Collaborative Innovation Center of Advanced Microstructures,Nanjing University,Nanjing 210000,China [2]School of Materials Science and Engineering,Peking University,Beijing 100871,China [3]College of Materials Science and Engineering,National Engineering Research Center for Magnesium Alloys,Chongqing University,Chongqing 400030,China [4]Center for High Pressure Science and Technology Advanced Research,Beijing 100094,China

出　　处：《Nano Research》2023年第1期1107-1114,共8页纳米研究（英文版）

基　　金：This research was supported by the National Natural Science Foundation of China(Nos.52072168,51861145201,21733001 and 91750101);the National Key R&D Program of China(Nos.2018YFA0306200 and 2021YFA1202901);Y.F.L.acknowledges financial support by the start-up fund from Chongqing University(No.02110011044171).

摘　　要：Light-matter interactions in low-dimensional quantum-confined structures can dominate the optical properties of the materials and lead to optoelectronic applications.In anisotropic layered silicon diphosphide(SiP2)crystal,the embedded quasi-onedimensional(1D)phosphorus–phosphorus(P–P)chains directly result in an unconventional quasi-1D excitonic state,and a special phonon mode vibrating along the P–P chains,establishing a unique 1D quantum-confined system.Alloying SiP2 with the homologous element serves as an effective way to study the properties of these excitons and phonons associated with the quasi-1D P–P chains,as well as the strong interaction between these quasiparticles.However,the experimental observation and the related optical spectral understanding of SiP2 with isoelectronic dopants remain elusive.Herein,with the photoluminescence and Raman spectroscopy measurements,we demonstrate the redshift of the confined excitonic peak and the stiffening of the phonon vibration mode■of a series of Si(P1−xAsx)2 alloys with increasing arsenic(As)compositions.This anomalous stiffening of■is attributed to the selective substitution of As atoms for P atoms within the P–P chains,which is confirmed via our scanning transmission electron microscopy investigation.Such optical spectra evolutions with selective substitution pave a new way to understand the 1D quantum confinement in semiconductors,offering opportunities to explore quasi-1D characteristics in SiP2 and the resulting photonic device application.

关 键 词：SiP2 quasi-one-dimensional structure Raman photoluminescence PHOSPHIDE 

分 类 号：O43[机械工程—光学工程]