Physical Review A
Maxwell-Bloch approach to excess quantum noise
S. M. Dutra, Krista Joosten, Gerard Nienhuis, N. J. van Druten, A. M. van der Lee, Martin P. van Exter, J. P. Woerdman
Abstract
To meet recent experimental advances, we generalize the intuitively appealing nonorthogonal-mode theory of excess quantum noise by introducing a Maxwell-Bloch description of the gain medium. The resulting equations extend the nonorthogonal-mode approach beyond the class A linear-gain regime providing a general starting point for theoretical descriptions of excess quantum noise. As an illustration of our theory, we derive rate equations describing excess quantum noise in class B lasers and obtain the non-Lorentzian spectrum due to the coloring of excess noise in class A lasers accounting for gain saturation.