Laser phase noise to intensity noise conversion by lowest-order group-velocity dispersion in optical fiber: exact theory

An exact result for the spectral density of intensity variations that occur after propagation of ergodic light in a medium having lowest-order-only gr oup-velocity dispersion is obtained and applied to the problem of semicondu ctor laser phase noise to intensity noise conversion in a single-mode optic al fiber. It is shown that the intensity spectrum after propagation formall y approaches, for a large laser linewidth or a long (or high-dispersion) fi ber, the intensity spectrum of a thermal source having the same Line shape as the laser. (C) 2000 Optical Society of America. OCIS codes: 060.2430, 14 0.5960, 260.2030, 270.2500, 060.5060.