2026-08-25 大阪大学
図. 色中心の発光過程（ΓZPL）と光損失過程（ΓNR）を説明する模式図
＜関連情報＞
- https://resou.osaka-u.ac.jp/ja/research/2026/20260825_1
- https://www.nature.com/articles/s41524-026-02267-8
発色中心における放射過程および非放射過程を予測するための統一的な第一原理フレームワーク Unified first-principles framework for predicting radiative and non-radiative processes in color centers
Sosuke Iwamoto,Masahiro Hara,Heiji Watanabe & Takuma Kobayashi
npj Computational Materials Published:25 August 2026
DOI:https://doi.org/10.1038/s41524-026-02267-8
Abstract
Uncovering promising spin-qubit candidates among a myriad of semiconductor point defects requires high-throughput screening based on first-principles calculations. In practice, however, assessing color centers must incorporate phonon-related quantities such as phonon-sideband emission and non-radiative transition rates, which makes the calculations considerably cumbersome. In this paper, we present a method that streamlines the computational steps required to include phonon contributions to both radiative and non-radiative processes. In evaluating the non-radiative transition rate, we simplify the original summation-based expression and obtained a compact, tractable closed-form formula in the low-temperature limit, assuming the electron-phonon coupling matrix element to be constant. Furthermore, we show that perturbative energy evaluations at displaced atomic configurations can be replaced by a much simpler computation of energetics within the single-phonon-mode approximation. We applied the methodology proposed here to impurity-vacancy defects in 4H-SiC and demonstrated that it is highly versatile, allowing straightforward application to a broad range of material systems beyond those examined in this study.
