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arXiv · 2603.25830

Scaling laws of electron and hole spin relaxation in indirect band gap (In,Al)As/AlAs quantum dots

T. S. Shamirzaev·D. R. Yakovlev·D. S. Smirnov·V. N. Mantsevich·M. Bayer
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Abstract

We investigate the electron and heavy hole spin dynamics as a function of magnetic field in ensembles of indirect band gap (In,Al)As/AlAs quantum dots (QDs) with type-I band alignment. Employing a comprehensive model that accounts for both the exciton level quartet and the magnetic-field-driven redistribution of excitons between these states via spin relaxation processes, we extract the electron ($\tau_{se}$) and heavy hole ($\tau_{sh}$) spin relaxation times as a function of magnetic field for QDs of varying sizes. Our analysis reveals that both $\tau_{se}(B)$ and $\tau_{sh}(B)$ exhibit power-law scaling behavior, yet the scaling exponents for electrons and heavy holes show markedly different evolution with QD size. For QDs with a diameter of about 9 nm, we find $\tau_{se}(B)\propto B^{-5}$ and $\tau_{sh}(B)\propto B^{-3}$. Remarkably, increasing the QD diameter to about 16 nm results in a drastic change of the scaling laws, with both $\tau_{se}(B)$ and $\tau_{sh}(B)$ following a $\propto B^{-9}$ dependence. We discuss the underlying mechanisms responsible for this size-dependent transformation of the magnetic field scaling behavior of carrier spin relaxation.

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T. S. Shamirzaev, D. R. Yakovlev, D. S. Smirnov, V. N. Mantsevich, M. Bayer. 2026-03-26. Scaling laws of electron and hole spin relaxation in indirect band gap (In,Al)As/AlAs quantum dots. https://arxiv.org/abs/2603.25830

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