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
2011 New Journal of Physics  
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
more » ... 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.
doi:10.1088/1367-2630/13/2/023007 fatcat:2qu2cib2jvabnhq4wefk57gvki