Physical Review A
Moving mirrors and time-varying dielectrics
Harry Johnston, Sarben Sarkar
Abstract
The spectral distribution of light generated by a finite cavity with one moving mirror is compared with that produced by a fixed cavity containing a time-varying dielectric. In both cases a motion over a finite time interval is considered. Although the moving mirror is usually considered to be an idealization for the time-varying dielectric, there are qualitative differences in the spectra produced. The spectral distribution for the moving mirror case behaves as 1/${\mathit{n}}^{3}$, while that for the time-varying dielectric behaves on average as 1/${\mathit{n}}^{4}$ but is rapidly oscillating.