Experimental quantum cosmology in time-dependent optical media

Abstract

It is possible to construct artificial spacetime geometries for light by using intense laser pulses that modify the spatiotemporal properties of an optical medium. Here we theoretically investigate experimental possibilities for studying spacetime metrics of the form $\text{d}{s}^2=c^2\text{d}{t}^2-\eta (t{)}^2\text{d}{x}^2$. By tailoring the laser pulse shape and medium properties, it is possible to create a refractive index variation $n=n(t)$ that can be identified with $\eta (t)$. Starting from a perturbative solution to a generalised Hopfield model for the medium described by an $n=n(t)$ we provide estimates for the number of photons generated by the time-dependent spacetime. The simplest example is that of a uniformly varying $\eta (t)$ that therefore describes the Robertson-Walker metric, i.e. a cosmological expansion. The number of photon pairs generated in experimentally feasible conditions appears to be extremely small. However, large photon production can be obtained by periodically modulating the medium and thus resorting to a resonant enhancement similar to that observed in the dynamical Casimir effect. Curiously, the spacetime metric in this case closely resembles that of a gravitational wave. Motivated by this analogy we show that a periodic gravitational wave can indeed act as an amplifier for photons. The emission for an actual gravitational wave will be very weak but should be readily observable in the laboratory analogue.

Version accepted fro publication in New Journal of Physics

References in corpus (22)

• Observation of the Dynamical Casimir Effect in a Superconducting Circuit
• Fiber-optical analogue of the event horizon
• Measurement of stimulated Hawking emission in an analogue system
• Stimulating uncertainty: Amplifying the quantum vacuum with superconducting circuits
• Hawking radiation from ultrashort laser pulse filaments
• Dynamical Casimir effect in a Josephson metamaterial
• Realization of a sonic black hole analogue in a Bose-Einstein condensate
• Motion Induced Radiation from a Vibrating Cavity
• Metric Signature Transitions in Optical Metamaterials
• An acoustic analog to the dynamical Casimir effect in a Bose-Einstein condensate
• The dynamical Casimir effect in superconducting microwave circuits
• Analogue models for FRW cosmologies
• Radio wave emissions due to gravitational radiation
• Dielectric black holes induced by a refractive index perturbation and the Hawking effect
• Analogue Casimir Radiation using an Optical Para- metric Oscillator
• Analogue Gravity and ultrashort laser pulse filamentation
• Cosmological Electromagnetic Fields due to Gravitational Wave Perturbations
• Blackbody emission from light interacting with an effective moving dispersive medium
• Frequency converter implementing an optical analogue of the cosmological redshift
• Spacetime geometries and light trapping in travelling refractive index perturbations
• Perturbative photon production in a dispersive medium
• Exact plane gravitational waves and electromagnetic fields

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• Time Circular Birefringence in Time-Dependent Magnetoelectric Media
• Quantum radiation in dielectric media with dispersion and dissipation
• Vacuum radiation and frequency-mixing in linear light-matter systems
• Non-linear media in weakly curved spacetime: optical solitons and probe pulses for gravimetry
• Correspondence between dark energy quantum cosmology and Maxwell equations