Amplification of the photocurrent in SiO2(Co)/GaAs heterostructure induced by magnetic field in the avalanche regime

V. V. Pavlov; L. V. Lutsev; P. A. Usachev; A. A. Astretsov; A. I. Stognij; N. N. Novitskii; R. V. Pisarev

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arXiv · 1212.6620

Amplification of the photocurrent in SiO2(Co)/GaAs heterostructure induced by magnetic field in the avalanche regime

V. V. Pavlov·L. V. Lutsev·P. A. Usachev·A. A. Astretsov·A. I. Stognij·N. N. Novitskii·R. V. Pisarev

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Abstract

Amplification of the photocurrent in heterostructures of silicon dioxide films containing cobalt nanoparticles grown on gallium arsenide SiO2(Co)/GaAs has been observed in magnetic field in the avalanche regime. While the avalanche process is suppressed by the magnetic field and the current decreases, for photon energy E greater than the GaAs bandgap energy the photocurrent significantly increases. The amplification reaches 9.5 for E = 1.50 eV. The effect of the photocurrent amplification is explained by the spin-dependent recombination process at deep impurity centers in GaAs.

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V. V. Pavlov, L. V. Lutsev, P. A. Usachev, A. A. Astretsov, A. I. Stognij, N. N. Novitskii, R. V. Pisarev. 2012-12-29. Amplification of the photocurrent in SiO2(Co)/GaAs heterostructure induced by magnetic field in the avalanche regime. https://arxiv.org/abs/1212.6620

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