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Coherent control of spontaneous emission in a four-level system

Abstract In this article we study the potential for coherently control spontaneous emission in a four-level scheme. Our control parameter is the relative phase of two laser fields having the same angular frequency. We investigate in detail the trapping conditions, the population dynamics and the behaviour of the (long time) spontaneous emission spectrum, which are now phase dependent. Inhibition of spontaneous emission and extreme spectral narrowing are shown as the relative phase is varied. Our results are interpreted using a dressed state analysis of the dynamics.