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arXiv · 1401.6222

Amplification of electromagnetic waves excited by a chain of propagating magnetic vortices in YBaCuO Josephson-junction arrays at 77K and above

Boris Chesca·Daniel John·Christopher J. Mellor
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Abstract

When a soliton propagates in a discrete lattice it excites small-amplitude linear waves in its wake. In a dc current-biased Josephson-junction (JJ) array these manifest as electromagnetic (EM) waves excited by a (magnetic field induced) chain of propagating magnetic vortices. When the vortex velocity and the phase velocity of one of the excited EM waves match, phase-locking occurs. This produces resonant steps in the current-voltage characteristics where amplification of EM radiation occurs. We report the first observation of phase-locking-induced amplification of EM radiation at 77K and above in JJ arrays made of high temperature superconductors.

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Boris Chesca, Daniel John, Christopher J. Mellor. 2014-01-24. Amplification of electromagnetic waves excited by a chain of propagating magnetic vortices in YBaCuO Josephson-junction arrays at 77K and above. https://doi.org/10.1088/0953-2048%2F27%2F8%2F085015

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