上海科技大学知识管理系统

We report a generalized auxiliary coherent medium theory to settle the longstanding challenge of Anderson-type off-diagonal disorder (AODD) for simulating disordered alloys. The AODD is transformed into a diagonal-like disorder with a weighted discrete distribution in an auxiliary medium. This approach is demonstrated for simulating the phonon spectral in NiFe and NiPt alloys, and it is found that accounting for AODD substantially enhances the phonon linewidth to agree well with the supercell and experimental results, compared to results with averaged-value ODD. This paper provides an effective approach to treat the large fluctuation in ODD in disordered materials, presenting an important progress for mean-field simulations in the embedding framework. © 2022 American Physical Society.