Effect of atomic recoil on the absorption spectrum of driven V-type atoms

A numerical method is developed for a V system driven by two counterpropaga ting laser fields in a momentum regime where a full quantum-mechanical trea tment of the atomic variables is necessary. This method is based on a trans formation by which integral equations, reduced from steady-state optical-Bl och-type equations involving the atomic center-of-mass momentum, can be tra nsformed into inhomogeneous tridiagonal vector recurrence equations. The ef fect of the atomic recoil on the momentum distribution in the absence of th e probe field, and, in particular, the absorption spectrum in a copropagati ng spectrum configuration is analyzed and discussed. Special attention is g iven to the Rayleigh resonance of subnatural linewidth. [S1050-2947(99)1011 2-4].