arXiv subjects

Maxime J Jacquet

Publications and source records attributed to Maxime J Jacquet.

10 recordsLinked to original sources

arXiv2025

Multiply quantized vortex spectroscopy in a quantum fluid of light

The formation of quantized vortices is a unifying feature of quantum mechanical systems, making it a premier means for fundamental and comparative studies of different quantum fluids. Being excited states of motion, vortices are normally unstable towards relaxation into lower energy states. However, here we exploit the driven-dissipative nature of polaritonic fluids of light to create stationary, multiply charged vortices. We measure the spectrum of collective excitations and observe negative energy modes at the core and positive energy modes at large radii. Their coexistence at the same frequency normally causes the dynamical instability, but here intrinsic losses stabilize the system, allowing for phase pinning by the pump on macroscopic scales. We observe generic features of quantized vortices in quantum fluids and other rotating geometries like astrophysical compact objects, opening the way to the study of generic amplification phenomena.

cond-mat.quant-gas↗

arXiv2025

Stimulated Hawking effect and quasinormal mode resonance in a polariton simulator of field theory on curved spacetime

The Hawking effect amplifies fluctuations in the vicinity of horizons, both in black holes and in analogue platforms. Here, we consider a polariton simulator and numerically examine the \emph{stimulated} Hawking effect using a coherent probe incident on the horizon from the exterior. We implement an experimentally realistic effective spacetime that supports a quasinormal mode (QNM) in the vicinity of the horizon. We find that the stimulated Hawking effect manifests as transmission into a negative-energy Bogoliubov channel inside the horizon, consistent with pseudo-unitary Bogoliubov scattering. Moreover, transmission across the horizon peaks at the QNM frequency. The computed spectral signatures provide a practical guide for future experimental investigations of the Hawking effect and its interplay with QNMs, an open question in quantum field theory in curved spacetime.

quant-ph↗

arXiv2024

Polariton Fluids as Quantum Field Theory Simulators on Tailored Curved Spacetimes

Quantum fields in curved spacetime exhibit a wealth of effects like Hawking radiation from black holes. While quantum field theory in black holes can only be studied theoretically, it can be tested in controlled laboratory experiments. In experiments, a fluid going from sub- to supersonic speed creates an effectively curved spacetime for the acoustic field, with a horizon where the speed of the fluid equals the speed of sound. The challenge to test predictions like the Hawking effect in such systems lies in the control of the spacetime curvature and access to the field spectrum thereon. Here, we create tailored stationary effective curved spacetimes in a polaritonic quantum fluid of light in which either massless or massive excitations can be created, with smooth and steep horizons and various supersonic fluid speeds. Using a recently developed spectroscopy method we measure the spectrum of collective excitations on these spacetimes, crucially observing negative energy modes in the supersonic regions, which signals the formation of a horizon. Control over the horizon curvature and access to the spectrum on either side demonstrates the potential of quantum fluids of light for the study of field theories on curved spacetimes, and we discuss the possibility of investigating emission and spectral instabilities with a horizon or in an effective Exotic Compact Object configuration.

cond-mat.quant-gas↗

arXiv2023

Analogue gravity and the Hawking effect: historical perspective and literature review

Reasoning by analogies permeates theoretical developments in physics and astrophysics, motivated by the unreachable nature of many phenomena at play. For example, analogies have been used to understand black hole physics, leading to the development of a thermodynamic theory for these objects and the discovery of the Hawking effect. The latter, which results from quantum field theory on black hole space-times, changed the way physicists approached this subject: what had started as a mere aid to understanding becomes a possible source of evidence via the research programme of `analogue gravity' that builds on analogue models for field effects. Some of these analogue models may and can be realised in the laboratory, allowing experimental tests of field effects. Here, we present a historical perspective on the connection between the Hawking effect and analogue models. We also present a literature review of current research, bringing history and contemporary physics together. We argue that the history of analogue gravity and the Hawking effect is divided into three distinct phases based on how and why analogue models have been used to investigate fields in the vicinity of black holes. Furthermore, we find that modern research signals a transition to a new phase, where the impetus for the use of analogue models has surpassed the problem they were originally designed to solve.

physics.hist-ph↗

arXiv2023

Quantum vacuum excitation of a quasi-normal mode in an analog model of black hole spacetime

Vacuum quantum fluctuations near horizons are known to yield correlated emission by the Hawking effect. We use a driven-dissipative quantum fluid of microcavity polaritons as an analog model of a quantum field theory on a black-hole spacetime and numerically calculate correlated emission. We show that, in addition to the Hawking effect at the sonic horizon, quantum fluctuations may result in a sizeable stationary excitation of a quasi-normal mode of the field theory. Observable signatures of the excitation of the quasi-normal mode are found in the spatial density fluctuations as well as in the spectrum of Hawking emission. This suggests an intrinsic fluctuation-driven mechanism leading to the quantum excitation of quasi-normal modes on black hole spacetimes.

gr-qc↗

arXiv2021

High-resolution coherent probe spectroscopy of a polariton quantum fluid

Characterising elementary excitations in quantum fluids is essential to study collective effects within. We present an original angle-resolved coherent probe spectroscopy technique to study the dispersion of these excitation modes in a fluid of polaritons under resonant pumping. Thanks to the unprecedented spectral and spatial resolution, we observe directly the low-energy phononic behaviour and detect the negative-energy modes, i.e. the \textit{ghost branch}, of the dispersion relation. In addition, we reveal narrow spectral features precursory of dynamical instabilities due to the intrinsic out-of-equilibrium nature of the system. This technique provides the missing tool for the quantitative study of quantum hydrodynamics in polariton fluids.

cond-mat.quant-gas↗

arXiv2020

The next generation of analogue gravity experiments

This article is an introduction for a theme issue following a Scientific Discussion Meeting on \emph{The next generation of analogue gravity experiments} held at the Royal Society in December 2019. This theme issue comprises a collection of recent advances of the research programme, as well as their philosophical implications, that were presented at the meeting.

gr-qc↗

arXiv2020

Analytical description of quantum emission in optical analogues to gravity

We consider a moving refractive index perturbation in an optical medium as an optical analogue to waves under the influence of gravity. We describe the dielectric medium by the Lagrangian of the Hopfield model. We supplement the field theory in curved spacetime for this model to solve the scattering problem for all modes and frequencies analytically. Because of dispersion, the kinematic scenario of the field modes may contain optical event horizons for some frequencies. We calculate the spectra of spontaneous emission in the frame co-moving with the perturbation and in the laboratory frame. We also calculate the spectrally-resolved photon number correlations in either frame. The emitted multimode field comes in different types depending on the presence of horizons. We show that these types are robust against changes in the system parameters and thus are genuine features of optical and non-optical analogues. These methods and findings pave the way to new observations of analogue gravity in dispersive systems.

quant-ph↗

arXiv2020

The influence of spacetime curvature on quantum emission in optical analogues to gravity

Quantum fluctuations on curved spacetimes cause the emission of pairs of particles from the quantum vacuum, as in the Hawking effect from black holes. We use an optical analogue to gravity to investigate the influence of the curvature on quantum emission. Due to dispersion, the spacetime curvature varies with frequency here. We analytically calculate for all frequencies the particle flux, correlations and entanglement. We find that horizons increase the flux with a characteristic spectral shape. The photon number correlations transition from multi- to two-mode, with close to maximal entanglement. The quantum state is a diagnostic for the mode conversion in laboratory tests of quantum field theory on curved spacetimes.

gr-qc↗

arXiv2020

Analytical description of spontaneous emission of light at the optical event horizon

Quantum fluctuations in curved space-time cause the emission of particles. In order to understand how they may be detected in a laboratory experiment, we consider a moving refractive index perturbation in an optical medium, which exhibits optical event horizons. Based on the field theory in curved space-time we formulate an analytical method to calculate the scattering matrix that completely describes mode coupling leading to the emission of photon pairs in various configurations. We then quantify the spectrally resolved photon number correlations. Moreover, we apply our method in a case study, in which we consider a moving refractive index step in bulk fused silica. We calculate key observables in the moving frame as well as in the laboratory frame, such as the emission spectrum and the spectrally resolved quantum correlations of the photon number. We observe significant spectral correlations between modes of opposite norm, evidence of their vacuum origin. We find that emission from horizons is characterised by an increased photon flux, a signature spectral shape as well as a correlation with the partner photon mode approaching unity. These methods and findings pave the way to the observation of particles from the event horizon in dispersive systems.

quant-ph↗