AnaBHEL (Analog Black Hole Evaporation via Lasers) Experiment: Concept, Design, and Status

Accelerating relativistic mirrors have long been recognized as viable settings where the physics mimic those of the black hole Hawking radiation. In 2017, Chen and Mourou proposed a novel method to realize such a system by traversing an ultra-intense laser through a plasma target with a decreasing density. An international AnaBHEL (Analog Black Hole Evaporation via Lasers) collaboration was formed with the objectives of observing the analog Hawking radiation, shedding light on the information loss paradox. To reach these goals, we plan to first verify the dynamics of the flying plasma mirror and characterize the correspondence between the plasma density gradient and the trajectory of the accelerating plasma mirror. We will then attempt to detect the analog Hawking radiation photons and measure the entanglement between the Hawking photons and their “partner particles”. In this paper, we describe our vision and strategy of AnaBHEL using the Apollon laser as a reference, and we report on the progress of our R&D concerning the key components in this experiment, including the supersonic gas jet with a graded density profile, and the superconducting nanowire single-photon Hawking detector. In parallel to these hardware efforts, we performed computer simulations to estimate the potential backgrounds, and derived analytic expressions for modifications to the blackbody spectrum of the Hawking radiation for a perfectly reflecting point mirror, due to the semi-transparency and finite-size effects specific to flying plasma mirrors. Based on this more realistic radiation spectrum, we estimate the Hawking photon yield to guide the design of the AnaBHEL experiment, which appears to be achievable.