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arXiv · 1102.2721

Sub-Wavelength Terahertz Spin-Flip Laser Based on a Magnetic Point-Contact Array

R. I. Shekhter·A. M. Kadigrobov·M. Jonson·E. I. Smotrova·A. I. Nosich·V. Korenivski
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Abstract

We present a novel design for a single-mode, truly sub-wavelength THz disk laser based on a nano-composite gain medium comprising an array of metal/ferromagnetic point contacts embedded in a thin dielectric layer. Stimulated emission of light occurs in the point contacts as a result of spin-flip relaxation of spin-polarized electrons that are injected from the ferromagnetic side of the contacts. Ultra-high electrical current densities in the contacts and a dielectric material with a large refractive index, neither condition being achievable in conventional semiconductor media, allows the thresholds of lasing to be overcome for the lowest-order modes of the disk, hence making single-mode operation possible.

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R. I. Shekhter, A. M. Kadigrobov, M. Jonson, E. I. Smotrova, A. I. Nosich, V. Korenivski. 2011-02-14. Sub-Wavelength Terahertz Spin-Flip Laser Based on a Magnetic Point-Contact Array. https://doi.org/10.1364/ol.36.002381

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