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arXiv · 2009.11183

Biorthogonal quantum criticality in non-Hermitian many-body systems

Gaoyong Sun·Jia-Chen Tang·Su-Peng Kou
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Abstract

We develop the perturbation theory of the fidelity susceptibility in biorthogonal bases for arbitrary interacting non-Hermitian many-body systems with real eigenvalues. The quantum criticality in the non-Hermitian transverse field Ising chain is investigated by the second derivative of ground-state energy and the ground-state fidelity susceptibility. We show that the system undergoes a second-order phase transition with the Ising universal class by numerically computing the critical points and the critical exponents from the finite-size scaling theory. Interestingly, our results indicate that the biorthogonal quantum phase transitions are described by the biorthogonal fidelity susceptibility instead of the conventional fidelity susceptibility.

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Gaoyong Sun, Jia-Chen Tang, Su-Peng Kou. 2020-09-23. Biorthogonal quantum criticality in non-Hermitian many-body systems. https://doi.org/10.1007/s11467-021-1126-1

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