Low-frequency analogue Hawking radiation: The Bogoliubov-de Gennes model

Coutant, Antonin; Weinfurtner, Silke

Abstract

We analytically study the low-frequency properties of the analogue Hawking effect in Bose-Einstein condensates. We show that in one-dimensional flows displaying an analogue horizon, the Hawking effect is dominant in the low-frequency regime. This happens despite non vanishing greybody factors, that is, the coupling of the Hawking mode and its partner to the mode propagating with the flow. To show this, we obtained analytical expressions for the scattering coefficients, in general flows and taking into account the full Bogoliubov dispersion relation. We discuss the obtained expressions for the greybody factors. In particular, we show that they can be significantly decreased if the flow obeys a conformal coupling condition. We argue that in the presence of a small but non-zero temperature, reducing greybody factors greatly facilitates the observation of entanglement, that is, establishing that the state of the Hawking mode and its partner is non-separable.

Citation

Coutant, A., & Weinfurtner, S. (2018). Low-frequency analogue Hawking radiation: The Bogoliubov-de Gennes model. Physical Review D, 97(2), https://doi.org/10.1103/PhysRevD.97.025006

• Journal Article Type: Article
• Acceptance Date: Dec 8, 2017
• Online Publication Date: Jan 8, 2018
• Publication Date: Jan 15, 2018
• Deposit Date: Jan 29, 2018
• Publicly Available Date: Jan 29, 2018
• Journal: Physical Review D
• Print ISSN: 2470-0010
• Electronic ISSN: 2470-0029
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 97
• Issue: 2
• DOI: https://doi.org/10.1103/PhysRevD.97.025006
• Public URL: https://nottingham-repository.worktribe.com/output/904593
• Publisher URL: https://journals.aps.org/prd/abstract/10.1103/PhysRevD.97.025006