Abstract

An accelerated mirror generates photons from vacuum. This process is known as Unruh radiation.¹ A uniform distribution of dielectric sheets spaced much less than a wavelength apart produces a net change in the effective index. When the sheets are displaced in a spatially periodic manner, a grating is formed. Motion of the sheets results in a time dependent (parametrically varying) grating that can produce squeezing. In this configuration, the squeezing is ascribed to Unruh radiation. A field analysis of moving dielectric sheets in the background of the zero-point fluctuation field is presented in this paper and shown to correspond to the Unruh formula. Recently, Yablonovitch proposed to use laser-generated exploding plasmas to simulate an accelerating mirror surface.² We propose another simulation of accelerating mirrors with laser light that could lead to a laboratory experiment. If a grating is produced in a nonlinear fiber ring resonator, with one port of the 50/50 beam splitter fed by the pump, the other used as the signal port, the Unruh radiation emerges from the signal port and the pump is separated out automatically.

© 1989 Optical Society of America