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Weak localization and antilocalization in semiconducting polymer sandwich devices

Ö. Mermer·M. Wohlgenannt·G. Veeraraghavan·T. L. Francis
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Abstract

We have performed magnetoresistance measurements on polyfluorene sandwich devices in weak magnetic fields as a function of applied voltage, device temperature (10K to 300K), film thickness and electrode materials. We observed either negative or positive magnetoresistance, dependent mostly on the applied voltage, with a typical magnitude of several percent. The shape of the magnetoresistance curve is characteristic of weak localization and antilocalization. Using weak localization theory, we find that the phase-breaking length is relatively large even at room temperature, and spin-orbit interaction is a function of the applied electric field.

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Ö. Mermer, M. Wohlgenannt, G. Veeraraghavan, T. L. Francis. 2003-12-08. Weak localization and antilocalization in semiconducting polymer sandwich devices. https://arxiv.org/abs/cond-mat/0312204

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