Spin-Injection Terahertz Radiation in Magnetic Junctions

Abstract:

Electromagnetic radiation of 1 - 10 THz range is observed at room temperature in a structure with a point contact between a ferromagnetic rod and a thin ferromagnetic film under electric current of high enough density. The radiation is due to nonequilibrium spin injection between the components of the structure. By estimates, the injection can lead to inverted population of the spin subbands. The radiation power exceeds by orders of magnitude the thermal background (with the Joule heating taking into account) and follows the current without inertia. Efficiency of the oscillator depends strongly on the material used and quantum efficiency may exceed the unity. It means the stimulated radiation processes play an important role.

• Periodical: Solid State Phenomena (Volume 190)
• Pages: 153-156
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.190.153
• Online since: June 2012
• Authors: S.G. Chigarev, E.M. Epshtein, Y.V. Gulyaev, I.V. Malikov, G.M. Mikhailov, V.G. Shofman, P.E. Zilberman
• Keywords: Effective Spin Temperature, Energy Splitting, Quantum Efficiency of the Radiation, Radiation Transitions between Subbands, S-D Exchange Interaction, Spin Injection by Current, Spin Subband Population, Stimulated Radiation Processes

References

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