Squeezed thermal radiation state in a Kerr-nonlinear black body

Zixia Wu, Ze Cheng, Yunxia Ping +1 more

Ze Cheng

We find that the photon system in the black body filled in its interior by a Kerr-nonlinear crystal is in a squeezed thermal radiation state, in which the photon system possesses a new kind of quasiparticles - nonpolaritons. The existence of nonpolaritons should be manifested by observing the predicted temperature dependence of the velocity and squeezing of nonpolaritons. The propagation velocity and noise properties of nonpolaritons constitute potentially novel and significant effects in solid-state quantum optics and hence these effects should have extensive application to fields of science and technology.

Ze Cheng

A photon blackbody field in Kerr nonlinear crystal is a squeezed thermal radiation state in which there is a new kind of quasi particle, the nonpolariton. A nonpolariton is a condensate of virtual nonpolar phonons, with a bare photon acting as the nucleus of condensation. The propagation velocity of nonpolaritons is a monotonically increasing function of temperature, and the noise of one quadrature phase in the squeezed thermal radiation state can be below the noise level in the vacuum state. The photon system undergoes a second-order phase transition from the normal to the squeezed thermal radiation state.

Zixia Wu, Ze Cheng, Yanmin Zhang +1 more

M.E. Marhic, Prem Kumar

Haruna Katayama

A black hole laser in analogues of gravity amplifies Hawking radiation, which is unlikely to be measured in real black holes, and makes it observable. There have been proposals to realize such black hole lasers in various systems. However, no progress has been made in electric circuits for a long time, despite their many advantages such as high-precision electromagnetic wave detection. Here we propose a black hole laser in Josephson transmission lines incorporating metamaterial elements capable of producing Hawking-pair propagation modes and a Kerr nonlinearity due to the Josephson nonlinear inductance. A single dark soliton obeying the nonlinear Schrödinger equation produces a black hole-white hole horizon pair that acts as a laser cavity through a change in the refractive index due to the Kerr effect. We show that the resulting laser is a squeezed-state laser characterized by squeezing parameters. We also evaluate the degree of quantum correlation between Hawking and its partner radiations using entanglement entropy which does not require simultaneous measurements between them. As a result, the obtained entanglement entropy depending on the soliton velocity provides strong evidence that the resulting laser is derived from Hawking radiation with quantum correlation generated by pair production from the vacuum.