Spin-phonon interaction is an important channel for spin and energy relaxation in magnetic insulators. Understanding this interaction is critical for developing magnetic insulator-based spintronic devices. Quantifying this interaction in yttrium iron garnet (YIG), one of the most extensively investigated magnetic insulators, remains challenging because of the large number of atoms in a unit cell. Here, we report temperature-dependent and polarization-resolved Raman measurements in a YIG bulk crystal. We first classify the phonon modes based on their symmetry. We then develop a modified mean-field theory and define a symmetry-adapted parameter to quantify spin-phonon interaction in a phonon-mode specific way for the first time in YIG. Based on this improved mean-field theory, we discover a positive correlation between the spin-phonon interaction strength and the phonon frequency.
@article{arxiv.2103.09038,
title = {Spin-Phonon Interaction in Yttrium Iron Garnet},
author = {Kevin S. Olsson and Jeongheon Choe and Martin Rodriguez-Vega and Guru Khalsa and Nicole A. Benedek and Bin Fang and Jianshi Zhou and Gregory A. Fiete and Xiaoqin Li},
journal= {arXiv preprint arXiv:2103.09038},
year = {2021}
}