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arXiv · 1912.07227

Resonant generation of $p$-wave Cooper pair in non-Hermitian Kitaev chain at exceptional point

X. M. Yang·Z. Song
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Abstract

We investigate a non-Hermitian extension of Kitaev chain by considering imaginary $p$-wave pairing amplitudes. The exact solution shows that the phase diagram consists two phases with real and complex \ Bogoliubov-de-gens spectra, associated with $\mathcal{PT}$-symmetry breaking, which is separated by a hyperbolic exceptional line. The exceptional points (EPs) correspond to a specific Cooper pair state $( 1+c_{k}^{\dagger }c_{-k}^{\dagger }) \left\vert 0\right\rangle $\ with movable $k$ when the parameters vary along the exceptional line. The non-Hermiticity around EP supports resonant generation of such a pair state from the vacuum state $% \left\vert 0\right\rangle $ of fermions via the critical dynamic process. In addition, we propose a scheme to generate a superconducting state through a dynamic method.

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X. M. Yang, Z. Song. 2019-12-16. Resonant generation of $p$-wave Cooper pair in non-Hermitian Kitaev chain at exceptional point. https://doi.org/10.1103/physreva.102.022219

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