Long time universality of black-hole lasers

Year: 2021

Authors: de Nova J.R.M., Palacios P.F., Carusotto I., Sols F.

Autors Affiliation: Departamento de Fnsica de Materiales, Universidad Complutense de Madrid, E-28040 Madrid, Spain; INO-CNR BEC Center and Dipartimento di Fisica, Università di Trento, I-38123 Povo, Italy

Abstract: For flowing quantum gases, it has been found that at long times an initial black-hole laser (BHL) configuration exhibits only two possible states: the ground state or a periodic self-oscillating state of continuous emission of solitons. So far, all the works on this subject are based on a highly idealized model, quite difficult to implement experimentally. Here we study the instability spectrum and the time evolution of a recently proposed realistic model of a BHL, thus providing a useful theoretical tool for the clear identification of black-hole lasing in future experiments. We further confirm the existence of a well-defined phase diagram at long times, which bespeaks universality in the long-time behavior of a BHL. Additionally, we develop a complementary model in which the same potential profile is applied to a subsonic homogeneous flowing condensate that, despite not forming a BHL, evolves toward the same phase diagram as the associated BHL model. This result reveals an even stronger form of robustness in the long-time behavior with respect to the transient, which goes beyond what has been described in the previous literature.

Journal/Review: NEW JOURNAL OF PHYSICS

Volume: 23 (2)      Pages from: 023040-1  to: 023040-14

More Information: We would like to devote this work to the memory of Renaud Parentani, with whom we enjoyed valuable discussions, especially during the visit of one of us (JRMdN) to Universite Paris-Saclay. We also thank Florent Michel for useful remarks during the mentioned visit. This work has been supported by Grant FIS2017-84368-P from Spain´s MINECO. IC acknowledges support from the European Union´s Horizon 2020 Research and Innovation Program under Grant Agreement No. 820392 (PhoQuS) and from the Provincia Autonoma di Trento.
KeyWords: black holes; quantum gases; analog gravity; atomtronics; solitons; lasers
DOI: 10.1088/1367-2630/abdce2