Various strategies for thermoelectric material optimization have been widely studied and used for promoting electrical transport and suppressing thermal transport. As a nontraditional method, pressure has shown great potential, as it has been applied to obtain a high thermoelectric figure of merit, but the microscopic mechanisms involved have yet to be fully explored. In this study, we focus on r-GeTe, a low-temperature phase of GeTe, and investigate the pressure effects on the electronic structure, electrical transport properties and anharmonic lattice dynamics based on density functional theory (DFT), the Boltzmann transport equations (BTEs) and perturbation theory. Electronic relaxation times are obtained based on the electron-phonon interaction and the constant relaxation time approximation. The corresponding electrical transport properties are compared with those obtained from previous experiments. Hydrostatic pressure is shown to increase valley degeneracy, decrease the band effective mass and enhance the electrical transport property. At the same time, the increase in the low-frequency phonon lifetime and phonon group velocity leads to an increase in lattice thermal conductivity under pressure. This study provides insight into r-GeTe under hydrostatic pressure and paves the way for a high-pressure strategy to optimize transport properties.

热电材料优化的各种策略已被广泛研究并用于促进电传输和抑制热传输。作为一种非传统方法，压力已显示出巨大的潜力，因为它已被应用于获得高热电品质因数，但所涉及的微观机制尚未得到充分探索。在这项研究中，我们专注于 r-GeTe，GeTe 的低温相，并基于密度泛函理论 (DFT)、玻尔兹曼传输方程 ( BTE）和微扰理论。电子弛豫时间是基于电子-声子相互作用和恒定弛豫时间近似值获得的。将相应的电传输特性与从以前的实验中获得的进行比较。静水压力会增加谷简并性，降低能带有效质量并增强电传输特性。同时，低频声子寿命和声子群速度的增加导致压力下晶格热导率的增加。这项研究提供了对静水压力下 r-GeTe 的深入了解，并为优化传输特性的高压策略铺平了道路。低频声子寿命和声子群速度的增加导致压力下晶格热导率的增加。这项研究提供了对静水压力下 r-GeTe 的深入了解，并为优化传输特性的高压策略铺平了道路。低频声子寿命和声子群速度的增加导致压力下晶格热导率的增加。这项研究提供了对静水压力下 r-GeTe 的深入了解，并为优化传输特性的高压策略铺平了道路。