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arXiv · 1910.14198

Spin-phonon relaxation from a universal \emph{ab initio} density-matrix approach

Junqing Xu·Adela Habib·Sushant Kumar·Feng Wu·Ravishankar Sundararaman·Yuan Ping
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Abstract

Designing new quantum materials with long-lived electron spin states urgently requires a general theoretical formalism and computational technique to reliably predict intrinsic spin relaxation times. We present a new, accurate and universal first-principles methodology based on Lindbladian dynamics of density matrices to calculate spin-phonon relaxation time ($τ_s$) of solids with arbitrary spin mixing and crystal symmetry. This method describes contributions of Elliott-Yafet (EY) and D'yakonov-Perel' (DP) mechanisms to spin relaxation for systems with and without inversion symmetry on an equal footing. We show that intrinsic spin and momentum relaxation times both decrease with increasing temperature; however, for the DP mechanism, spin relaxation time varies inversely with extrinsic scattering time. We predict large anisotropy of spin lifetime in transition metal dichalcogenides. The excellent agreement with experiments for a broad range of materials underscores the predictive capability of our method for properties critical to quantum information science.

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Junqing Xu, Adela Habib, Sushant Kumar, Feng Wu, Ravishankar Sundararaman, Yuan Ping. 2020-04-03. Spin-phonon relaxation from a universal \emph{ab initio} density-matrix approach. https://doi.org/10.1038/s41467-020-16063-5

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