Microwave Kerr/Faraday Resonance in Two-dimensional Chiral Superconductors

Taiki Matsushita; Jun'ichi Ieda; Yasufumi Araki; Takahiro Morimoto; Ilya Vekhter; Youichi Yanase

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arXiv · 2601.10151

Microwave Kerr/Faraday Resonance in Two-dimensional Chiral Superconductors

Taiki Matsushita·Jun'ichi Ieda·Yasufumi Araki·Takahiro Morimoto·Ilya Vekhter·Youichi Yanase

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Abstract

We investigate the polar Kerr and Faraday effects in two-dimensional multiband chiral superconductors. We show that the clapping modes--the relative phase and amplitude oscillations between two chiral components of the superconducting order parameter--lie well within the quasiparticle excitation gap in multiband systems and dominate these magneto-optical responses in the microwave regime. The Kerr and Faraday rotation angles exhibit the resonant enhancement with sign reversals in the microwave regime as a function of the light frequency, reaching peak values on the order of 100 nrad--10 $\mu$rad in thin films of candidate chiral superconductors. These resonances are accessible in superconducting atomic layer materials and provide a generic probe of chiral superconductivity in two-dimensional systems.

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Taiki Matsushita, Jun'ichi Ieda, Yasufumi Araki, Takahiro Morimoto, Ilya Vekhter, Youichi Yanase. 2026-01-15. Microwave Kerr/Faraday Resonance in Two-dimensional Chiral Superconductors. https://arxiv.org/abs/2601.10151

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