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arXiv · 0809.3209

Compact cryogenic Kerr microscope for time-resolved studies of electron spin transport in microstructures

P. J. Rizo·A. Pugžlys·J. Liu·D. Reuter·A. D. Wieck·C. H. van der Wal·P. H. M. van Loosdrecht
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Abstract

A compact cryogenic Kerr microscope for operation in the small volume of high-field magnets is described. It is suited for measurements both in Voigt and Faraday configuration. Coupled with a pulsed laser source, the microscope is used to measure the time-resolved Kerr rotation response of semiconductor microstructures with ~1 micron spatial resolution. The microscope was designed to study spin transport, a critical issue in the field of spintronics. It is thus possible to generate spin polarization at a given location on a microstructure and probe it at a different location. The operation of the microscope is demonstrated by time-resolved measurements of micrometer distance diffusion of spin polarized electrons in a GaAs/AlGaAs heterojunction quantum well at 4.2 K and 7 Tesla.

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P. J. Rizo, A. Pugžlys, J. Liu, D. Reuter, A. D. Wieck, C. H. van der Wal, P. H. M. van Loosdrecht. 2008-09-18. Compact cryogenic Kerr microscope for time-resolved studies of electron spin transport in microstructures. https://doi.org/10.1063/1.3046283

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