Abstract

Whereas the regime of stimulated emission is safely classical for all existing and almost all proposed FELs, there is still some controversy as to the significance of quantum mechanical vacuum field fluctuations during the start-up, i.e., in particular in spontaneous emission. Also, there is no general agreement whether the initial fluctuations of the laser field intensity should be attributed to the stochastic character of spontaneous emission or to shot noise fluctuations in the electron current or, more precisely, which mechanism is dominant in which conditions.¹

© 1984 Optical Society of America