Smart Holes: Analogue black holes with the right temperature and entropy

TL;DR

This paper proposes that 2D tilted Dirac cone materials can serve as analogue black holes, replicating key features like temperature and entropy, thus enabling laboratory studies of quantum black hole phenomena.

Contribution

It introduces the concept of 'smart holes' in condensed matter systems that mimic black hole entropy and temperature, advancing analogue gravity research.

Findings

Entropy in these systems matches black hole Bekenstein-Hawking entropy.

Entropy concentrates near the analogue horizon where tilt parameter is close to one.

Nonlinear effects lead to entropy peaking in a Fermi puddle behind the horizon.

Abstract

In analogue gravity studies, the goal is to replicate black hole phenomena, such as Hawking radiation, within controlled laboratory settings. In the realm of condensed matter systems, this may happen in 2D tilted Dirac cone materials based on honeycomb lattice. In particular, we compute the entropy of this system, and find it has the same form as black hole Bekenstein-Hawking entropy, if an analogue horizon forms. Hence, these systems can be potential analogues of quantum black holes. We show that this entropy is primarily concentrated in the region where the tilt parameter is close to one, which corresponds to the location of the analogue black hole horizon. Additionally, when nonlinear effects are taken into account, the entropy is peaked in a small pocket of the Fermi sea that forms behind the analogue event horizon, which we call the \textit{Fermi puddle}. We further refer to this new type of analogue black hole as a {\it smart hole}, since, in contrast to dumb holes, it can simulate both the correct temperature {\it and} entropy of general relativistic black holes. These results provide an opportunity to illuminate various quantum facets of black hole physics in a laboratory setting.