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Using single quantum states as spin filters to study spin polarization in ferromagnets

Mandar M. Deshmukh·D. C. Ralph
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Abstract

By measuring electron tunneling between a ferromagnet and individual energy levels in an aluminum quantum dot, we show how spin-resolved quantum states can be used as filters to determine spin-dependent tunneling rates. We also observe magnetic-field-dependent shifts in the magnet's electrochemical potential relative to the dot's energy levels. The shifts vary between samples and are generally smaller than expected from the magnet's spin-polarized density of states. We suggest that they are affected by field-dependent charge redistribution at the magnetic interface.

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Mandar M. Deshmukh, D. C. Ralph. 2002-07-13. Using single quantum states as spin filters to study spin polarization in ferromagnets. https://doi.org/10.1103/physrevlett.89.266803

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