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arXiv · 2203.06693

Continuum damping of topologically-protected edge modes at the boundary of a magnetized plasma

Roopendra Singh Rajawat·V. Khudik·G. Shvets
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Abstract

Recent extension of the topological ideas to continuous systems with broken time-reversal symmetry, such as magnetized plasmas, provides new insights into the nature of scattering-free topologically-protected surface plasma waves (TSPWs). We demonstrate a unique characteristic of TSPWs propagating above the electron cyclotron frequency: their collisionless damping via coupling to the continuum of resonant modes localized inside a smooth plasma-vacuum interface. Damped TSPWs retain their unidirectional nature and robustness against backscattering. When sheared magnetic field creates a boundary between damped and undamped TSPWs, the two refract into each other without reflections

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Roopendra Singh Rajawat, V. Khudik, G. Shvets. 2022-03-13. Continuum damping of topologically-protected edge modes at the boundary of a magnetized plasma. https://doi.org/10.1103/physrevlett.134.055301

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