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arXiv · 2311.03047

Hole spin coherence in InAs/InAlGaAs self-assembled quantum dots emitting at telecom wavelengths

E. Evers·N. E. Kopteva·V. Nedelea·A. Kors·R. Kaur·J. P. Reithmaier·M. Benyoucef·M. Bayer·A. Greilich
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Abstract

We report measurements of the longitudinal and transverse spin relaxation times of holes in an ensemble of self-assembled InAs/InAlGaAs quantum dots (QDs), emitting in the telecom spectral range. The spin coherence of a single carrier is determined using spin mode-locking in the inhomogeneous ensemble of QDs. Modeling the signal allows us to extract the hole spin coherence time to be in the range of T$_2 = 0.02-0.4$ $μ$s. The longitudinal spin relaxation time T$_1 = 0.5$ $μ$s is measured using the spin inertia method.

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E. Evers, N. E. Kopteva, V. Nedelea, A. Kors, R. Kaur, J. P. Reithmaier, M. Benyoucef, M. Bayer, A. Greilich. 2023-11-06. Hole spin coherence in InAs/InAlGaAs self-assembled quantum dots emitting at telecom wavelengths. https://doi.org/10.1002/pssb.202400174

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