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arXiv · 0807.3082

Angular dependence of the radiation power of a Josephson STAR-emitter

Richard A. Klemm·Kazuo Kadowaki
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Abstract

We calculate the angular dependence of the power of stimulated terahertz amplified radiation (STAR) emitted from a $dc$ voltage applied across a stack of intrinsic Josephson junctions. During coherent emission, we assume a spatially uniform $ac$ Josephson current density in the stack acts as a surface electric current density antenna source, and the cavity features of the stack are contained in a magnetic surface current density source. A superconducting substrate acts as a perfect magnetic conductor with $H_{||,ac}=0$ on its surface. The combined results agree very well with recent experimental observations. Existing Bi$_2$Sr$_2$CaCu$_2$O$_{8+δ}$ crystals atop perfect electric conductors could have Josephson STAR-emitter power in excess of 5 mW, acceptable for many device applications.

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Richard A. Klemm, Kazuo Kadowaki. 2009-08-19. Angular dependence of the radiation power of a Josephson STAR-emitter. https://doi.org/10.1007/s10948-010-0719-7

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