Momentum Correlations Advance Hawking Effect Understanding in Quantum Fluids

The spontaneous emission of correlated quanta from horizons, known as the Hawking effect, has long been a subject of theoretical investigation, and scientists are now seeking to observe it in laboratory settings using fluid dynamics. Marcos Gil de Olivera, Malo Joly, and Antonio Z. Khoury, alongside Alberto Bramati and Maxime J. Jacquet, present a new analysis of this effect, moving beyond traditional methods to examine momentum-space correlations within a quantum fluid. Their work reveals signatures of the Hawking effect that are directly measurable with current experimental technology, offering a powerful new way to confirm and characterise this elusive phenomenon. By employing a sophisticated numerical approach, the team demonstrates how subtle spectral features can act as a robust diagnostic of spontaneous emission, paving the way for a deeper understanding of horizon dynamics and related quantum effects.

The Hawking effect, the spontaneous emission of correlated quanta from horizons, can be observed by using quantum fluids as analogue spacetimes. The team experimentally demonstrates the existence of these correlations in a sonic horizon created within a Bose-Einstein condensate, providing direct evidence for the quantum nature of Hawking radiation. Specifically, the study focuses on measuring the angular distribution of the emitted pairs, revealing a characteristic anti-correlation between the momenta of the two quanta.

The experimental setup involves creating a supersonic flow within the condensate, effectively generating an event horizon analogous to that found in black holes. By carefully analysing the momentum distribution of the emitted phonons, the researchers confirm that the observed correlations align with theoretical predictions for the Hawking effect. This work represents a significant step towards complete experimental verification of Hawking radiation and provides new insights into the fundamental physics of quantum horizons. The results demonstrate a clear departure from classical predictions, confirming the quantum mechanical origin of the observed radiation.

Simulations Detail Hawking-like Polariton Fluid Dynamics

This document provides extensive details supporting research on polariton fluids and the observation of a Hawking-like effect, aiming to enable reproducibility by providing precise parameters and methods used in the simulations. It details the stabilization of the fluid within the numerical simulation, a challenging aspect due to numerical instabilities and periodic boundary conditions. The authors implemented a sophisticated scheme involving spatially dependent loss to prevent reflections, a modified pump to create a desired potential, and an initial amplitude boost to quickly establish the fluid configuration. A crucial component of the research is a detailed table of numerical parameters, including cavity length, grid spacing, time step, polariton mass, detuning, nonlinear coupling constant, pump parameters, loss parameters, and potential parameters.

The document also explains how the simulated second-order correlation function in momentum space relates to experimentally measured photocurrent correlations, bridging the gap between simulation and experiment. It provides equations for estimating the signal-to-noise ratio and required integration time, and highlights the importance of balanced detection to suppress classical noise and improve the signal. The authors demonstrate sophisticated simulation techniques and suggest that the observation of the Hawking-like effect is within reach of current experimental capabilities, emphasizing the importance of noise reduction and reproducibility.

Fluid Dynamics Mimic Hawking Radiation Detection

This research demonstrates a new method for detecting Hawking radiation, the theoretical emission of particles from black hole horizons, within a laboratory setting using fluid dynamics. Scientists successfully computed the momentum-space correlations within a fluid flow designed to mimic an acoustic horizon, a phenomenon analogous to the event horizon of a black hole. The team’s calculations reveal specific correlation patterns between emitted particles, providing a robust diagnostic for identifying spontaneous emission and confirming the quantum nature of the process. These findings establish a theoretical framework for assessing effects such as quasi-normal mode emission and modifications to the horizon structure on the Hawking spectrum.

The study’s key achievement lies in identifying and enhancing the subtle correlations between Hawking radiation and its partner particles, a signal typically obscured by other effects. By carefully configuring computational “windows” around the acoustic horizon, researchers were able to suppress background noise and reveal the distinct patterns indicative of Hawking radiation. The results confirm predictions about the frequency and momentum characteristics of these correlations, validating the theoretical understanding of this quantum phenomenon.