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arXiv · 1806.03092

Optically-detected long-lived spin coherence in multilayer systems: Double and triple quantum wells

S. Ullah·G. M. Gusev·A. K. Bakarov·F. G. G. Hernandez
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Abstract

In this contribution, we investigated the spin coherence of high-mobility dense two-dimensional electron gases confined in multilayer systems. The dynamics of optically-induced spin polarization was experimentally studied employing the time-resolved Kerr rotation and resonant spin amplification techniques. For both the double and triple quantum wells doped beyond the metal-insulator transition, where the spin coherence is greatly suppressed, we found remarkably long spin lifetimes limited by the Dyakonov-Perel mechanism and spin hopping process between the donor sites as well as the spread of ensemble g-factor. The double quantum well structure yields a spin lifetime of 6.25 ns at T = 5 K while the triple quantum well shows a spin lifetime exceeding 25 ns at T = 8 K.

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S. Ullah, G. M. Gusev, A. K. Bakarov, F. G. G. Hernandez. 2018-06-08. Optically-detected long-lived spin coherence in multilayer systems: Double and triple quantum wells. https://arxiv.org/abs/1806.03092

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