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arXiv · 1101.2862

Hot electrons in magnetic point contacts as a photon source

A. M. Kadigrobov·R. I. Shekhter·S. I. Kulinich·M. Jonson·O. P. Balkashin·V. V. Fisun·Yu. G. Naidyuk·I. K. Yanson·S. Andersson·V. Korenivski
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Abstract

We propose to use a point contact between a ferromagnetic and a normal metal in the presence of a magnetic field for creating a large inverted spin-population of hot electrons in the contact core. The key point of the proposal is that when these hot electrons relax by flipping their spin, microwave photons are emitted, with a frequency tunable by the applied magnetic field. While point contacts is an established technology their use as a photon source is a new and potentially very useful application. We show that this photon emission process can be detected by means of transport spectroscopy and demonstrate stimulated emission of radiation in the 10-100 GHz range for a model point contact system using a minority-spin ferromagnetic injector. These results can potentially lead to new types of lasers based on spin injection in metals.

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A. M. Kadigrobov, R. I. Shekhter, S. I. Kulinich, M. Jonson, O. P. Balkashin, V. V. Fisun, Yu. G. Naidyuk, I. K. Yanson, S. Andersson, V. Korenivski. 2011-01-14. Hot electrons in magnetic point contacts as a photon source. https://doi.org/10.1088/1367-2630%2F13%2F2%2F023007

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