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arXiv · 0807.2660

Dynamics of Photo-excited Spins in InSb Based Quantum Wells

K. Nontapot·R. N. Kini·B. Spencer·G. A. Khodaparast·N. Goel·S. J. Chung·T. D. Mishima·M. B. Santos
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Abstract

We report time resolved measurements of spin relaxation in doped and undoped InSb quantum wells using degenerate and two-color magneto-optical Kerr effect techniques. We observed that the photo-excited spin dynamics are strongly influenced by laser excitation fluence and the doping profile of the samples. In the low fluence regime, an oscillatory pattern was observed at low temperatures ($\leq$ 77 K) in the samples with an asymmetric doping profile which might be attributed to the quasi-collision-free spin relaxation regime. Our measurements also suggest the influence of the barrier materials (Al$_{x}$In$_{1-x}$Sb) on the spin relaxation in these material systems.

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K. Nontapot, R. N. Kini, B. Spencer, G. A. Khodaparast, N. Goel, S. J. Chung, T. D. Mishima, M. B. Santos. 2008-07-16. Dynamics of Photo-excited Spins in InSb Based Quantum Wells. https://arxiv.org/abs/0807.2660

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