Khanmohammadi Sepideh, Kushnir Friedman Kateryna, Chen Ethan, Kastuar Srihari M, Ekuma Chinedu E, Koski Kristie J, Titova Lyubov V
Department of Physics, Worcester Polytechnic Institute, Worcester, Massachusetts 01609, United States.
Department of Chemistry, University of California Davis, Davis, California 95616, United States.
ACS Appl Mater Interfaces. 2024 Apr 3;16(13):16445-16452. doi: 10.1021/acsami.3c19251. Epub 2024 Mar 25.
Zero-valent intercalation of atomic metals into the van der Waals gap of layered materials can be used to tune their electronic, optical, thermal, and mechanical properties. Here, we report the impact of intercalating ∼3 atm percent of zero-valent copper into germanium sulfide (GeS). Advanced many-body calculations predict that copper introduces quasi-localized intermediate band states, and time-resolved THz spectroscopy studies demonstrate that those states have prominent effects on the photoconductivity of GeS. Cu-intercalated GeS exhibits a faster rise of transient photoconductivity and a shorter lifetime of optically injected carriers following near-gap excitation with 800 nm pulses. At the same time, Cu intercalation improves free carrier mobility from 1100 to 1300 cm V s, which we attribute to the damping of acoustic phonons observed in Brillouin scattering and consequent reduction of phonon scattering.
将零价原子金属插入层状材料的范德华间隙可用于调节其电子、光学、热学和力学性能。在此，我们报告了向硫化锗（GeS）中插入约3个大气压百分比的零价铜的影响。先进的多体计算预测，铜会引入准局域中间带态，时间分辨太赫兹光谱研究表明，这些态对GeS的光电导率有显著影响。铜插层的GeS在800 nm脉冲近带隙激发后，表现出更快的瞬态光电导率上升和光注入载流子更短的寿命。同时，铜插层将自由载流子迁移率从1100提高到1300 cm V s，我们将其归因于布里渊散射中观察到的声学声子的阻尼以及随之而来的声子散射的减少。
