title: Conservative form of the density of states of a photonic crystal with a pseudogap.
abstract: We show that the total number of states in a photonic crystal in the entire allowed frequency regime will be conserved, and it is equal to that of its corresponding effective medium, i.e., if the density of states (DOS) has a valley(s) in some range(s) of frequencies, it must be compensated for by increases over some other range(s). This rule is of importance in developing a model pseudogap in order to describe the mean emission characteristics of the system when there is a collection of dependently emitting atoms or molecules with essentially random dipole orientations in a large volume and the spectrum of the active atoms is wide enough. This is because, with this rule, the states-conservative model always results in DOS-induced suppression, absolute enhancement, narrowing, spectrum splits, and redshift or blueshift of spontaneous-emission spectra.
authors.affiliation: Optical Physics Laboratory, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China.
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: Liu
authors.forename: Yi-Quan
authors.initials: YQ
authors.lastname: Wang
authors.forename: Bing-Ying
authors.initials: BY
authors.lastname: Cheng
authors.forename: Dao-Zhong
authors.initials: DZ
authors.lastname: Zhang