Zhang Liang, Cai Yuhang, Li Long, Feng Wenshuai, Wen Rui-Tao, Shin Sunmi, Guo Liang
Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, China.
Department of Mechanical Engineering, National University of Singapore, Singapore.
Photoacoustics. 2023 Apr 7;30:100489. doi: 10.1016/j.pacs.2023.100489. eCollection 2023 Apr.
Acoustic deformation potential (ADP) plays a significant role in quantifying carrier-acoustic phonon interactions in semiconductors. In this work, we report a novel ultrafast spectroscopy method to extract the ADP coupling constant of a semiconductor by jointly analyzing the coherent acoustic phonon signals with and without a metal transducer. By applying this method to GaAs, the ADP coupling constant corresponding to the band gap was extracted using a pump photon energy near the band gap, which agrees well with literature values. With a larger pump photon energy, the ADP coupling constant deviates from the one for the band gap, which is attributed to contributions from the carrier dynamics in multiple energy and wavevector states.
声学形变势(ADP)在量化半导体中载流子与声子相互作用方面起着重要作用。在这项工作中,我们报告了一种新颖的超快光谱方法,通过联合分析有无金属换能器时的相干声子信号来提取半导体的ADP耦合常数。将该方法应用于砷化镓(GaAs),利用带隙附近的泵浦光子能量提取了对应于带隙的ADP耦合常数,其与文献值吻合良好。当泵浦光子能量较大时,ADP耦合常数偏离带隙对应的常数,这归因于多个能量和波矢状态下的载流子动力学贡献。