Japanese Journal of Applied Physics

Theory of a One-Dimensional Laser with Output Coupling –Linear Theory–

Kikuo Ujihara

Published Aug 1, 1976• 16 citations

Abstract

The spatial behavior of the field of a one-dimensional laser having a partial transmission in its cavity wall is analysed. The partial transmission allows coupling between the field inside the laser cavity and that of outer space (output coupling). A formulation is developed in which the field is described in terms of many normal modes of the "universe", i.e. , the whole space incluing the cavity. The transient building-up of the field is considered under the assumption that the atoms have a constant population inversion. Noise is ignored. The equations for the modes of the universe are converted into a single equation for the electric field which displays very clearly the space-time structure of the laser action. Cavity resonant modes (lossy quasi-modes) are shown to be excited and to produce outgoing waves outside the cavity. The threshold population inversion and the oscillation frequency at the threshold are derived.

DOI: 10.1143/jjap.15.1529

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