High-Throughput Computational Analysis of the Role of Finite Temperature in the Optical Response of 2D Materials

Stable two-dimensional materials are promising for nanoelectronic applications due to their relatively small form factor, and their great variety of chemical and optoelectronic properties [1]. This allows for the design of light-weight and low-cost materials for optoelectronic devices for applications such as single-electron transistors [2], solar cells [3], and lasers [4]. Here, we utilize first-principles density functional theory (DFT) to investigate the optoelectronic function of these monolayer materials, including the role of electron-phonon interactions.

DFT is the standard modeling methodology for studying the electronic properties of solid-state materials. However, the common T = 0K approximation may result in an erroneous understanding of the material properties [5]. This is especially the case for low-dimensional materials with low-screening that results in increased electron-phonon interactions [6]. We present a high-throughput DFT and beyond-DFT approach to study of the effect of finite temperature on the optical properties of 2D materials, incorporating the role of phonons through a semi-classical approach [7]. We show that the strength of electron-phonon interactions is highly dependent on the bond ionicity within the crystal. We show that this framework allows for a systematic theoretical exploration of new materials for solar energy conversion.

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