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arXiv · 1907.03509

Hairy BTZ black hole and its analogue model in graphene

Abstract

We obtain a novel exact analytical solution to Einstein-Maxwell-scalar gravity with negative cosmological constant in (2+1)-dimensions. The scalar field is minimally coupled to gravity and electromagnetism by the metric ansatz. On the one hand, we first find analytical results for the real part of quasinormal mode spectrum of a rotating hairy Bañados-Teitelboim-Zanelli (BTZ) black hole by solving the associated Dirac equation through the pseudo-Hermitian quantum mechanical tools within the framework of discrete-basis-set method. We then show that, in the spinless case, these quasinormal modes (QNMs) have equally spaced with respect to the related azimuthal quantum number, while the spinning BTZ black hole with scalar hair has Dirac-like unequally spaced discrete one. Moreover, the analytical results for these QNMs found here are in excellent agreement with those found in the literature for hairless BTZ black holes. On the other hand, we also develop an analogue model for this hairy Banados-Teitelboim-Zanelli black hole in graphene, by mapping it onto the hyperbolic pseudosphere surface with negative curvature. The model not only offers to make some predictions for the gravity-like phenomena in a curved graphene sheet but also paves the way for reproducing black hole thermodynamics scenarios in two-dimensional topological insulators.

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BibTeXRIS

B. S. Kandemir. 2019-07-08. Hairy BTZ black hole and its analogue model in graphene. https://doi.org/10.1016/j.aop.2019.168064

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