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Spin transfer and coherence in coupled quantum wells

M. Poggio·G. M. Steeves·R. C. Myers·N. P. Stern·A. C. Gossard·D. D. Awschalom
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Abstract

Spin dynamics of optically excited electrons confined in asymmetric coupled quantum wells are investigated through time resolved Faraday rotation experiments. The inter-well coupling is shown to depend on applied electric field and barrier thickness. We observe three coupling regimes: independent spin precession in isolated quantum wells, incoherent spin transfer between single-well states, and coherent spin transfer in a highly coupled system. Relative values of the inter-well tunneling time, the electron spin lifetime, and the Larmor precession period appear to govern this behavior.

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M. Poggio, G. M. Steeves, R. C. Myers, N. P. Stern, A. C. Gossard, D. D. Awschalom. 2004-06-27. Spin transfer and coherence in coupled quantum wells. https://doi.org/10.1103/physrevb.70.121305

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