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arXiv · 1807.07504

Quantum Simulation of Coherent Hawking-Unruh Radiation

Jiazhong Hu·Lei Feng·Zhendong Zhang·Cheng Chin
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Abstract

Exploring quantum phenomena in a curved spacetime is an emerging interdisciplinary area relating many fields in physics such as general relativity, thermodynamics, and quantum information. One famous prediction is the Hawking-Unruh thermal radiation, the manifestation of Minkowski vacuum in an accelerating reference frame. We simulate the radiation by evolving a parametrically driven Bose-Einstein condensate of $\approx 10^5$ atoms, which radiates coherent pairs of atoms with opposite momenta. We observe a matterwave field which follows a Boltzmann distribution for a local observer. The extracted temperature and entropy from the atomic distribution are in agreement with Unruh's predictions. We further observe the long-distance phase coherence and temporal reversibility of emitted matter-waves, hallmarks that distinguish Unruh radiations from classical counterparts. Our results may lead to further insights regarding the nature of the Hawking and Unruh effects and behaviors of quantum physics in a curved spacetime.

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Jiazhong Hu, Lei Feng, Zhendong Zhang, Cheng Chin. 2018-07-19. Quantum Simulation of Coherent Hawking-Unruh Radiation. https://doi.org/10.1038/s41567-019-0537-1

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