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arXiv · 1903.10886

Quantum chaos associated with emergent ergosurface in transition layer between type-I and type-II Weyl semimetals

Yu-Ge Chen·Xi Luo·Fei-Ye Li·Bin Chen·Yue Yu
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Abstract

We present emergent ergosurfaces (ES) in a transition layer between type-I and type-II Weyl semimetals (WSMs). The Hawking temperature defined by the surface gravity at the acoustic event horizon which coincides with the ES when the tangent velocity $v_{\parallel}$ is small is in a measurable interval. On the type-II WSM side, i.e., inside the {ES when $v_{\parallel}$ is large}, the motion of the quasiparticles may be chaotic {after} a critical surface as they are governed by an effective inverted oscillator potential induced by the mismatch between the type-I and type-II Weyl nodes. In a relevant lattice model, we calculate out of time ordered correlators (OTOCs). We find that the OTOCs are fast scrambling with a quantum Lyapunov exponent in high temperature and the scrambling is saturated after the Ehrenfest time. This confirms the quantum chaotic behavior.

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Yu-Ge Chen, Xi Luo, Fei-Ye Li, Bin Chen, Yue Yu. 2019-03-26. Quantum chaos associated with emergent ergosurface in transition layer between type-I and type-II Weyl semimetals. https://doi.org/10.1103/physrevb.101.035130

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