Journal of Modern Optics
Exact trapping state dynamics for the 85Rb atom micromaser at very high Q and/or very low T
Amitabh Joshi
Abstract
Matrix continued fraction methods pioneered previously [1–3] are used to solve essentially exactly the dynamics of the one 85Rb atom micromaser. Ranges of cavity Q values, of average atomic input rates R = T p −1 and of atomic interaction times t int are studied with the principal aim of minimizing the cavity field variance v. As expected for T p ≳ 200t int the system does evolve to a steady state with v < 1 and sub-Poissonian photon statistics. But even Q = 5 × 1010 and temperature T = 0·070 K are apparently insufficient conditions for avoiding evolution to a steady state with v < 0 when t int = 1·54/(44 kHz) unless T p is also substantially reduced. Only in this way is actual trapping state dynamics obtained for this value of t int, while no example is found where the system evolves to v = 0 and a single Fock state is produced. The field variance v considered alone is not a good diagnostic for observing such trapping state dynamics and more information will be needed in order to describe adequately the cavity field.