S. Sultana et Ms. Zubairy, EFFECT OF FINITE BANDWIDTH ON REFRACTIVE-INDEX ENHANCEMENT AND LASINGWITHOUT INVERSION, Physical review. A, 49(1), 1994, pp. 438-448
We have studied the effect of finite bandwidth of the driving field on
the enhancement of refractive index and lasing without inversion in a
three-level atomic system in which partial coherence is introduced ei
ther in upper-level or lower-level doublet via a strong microwave driv
ing field having finite bandwidth. We find that both phenomena are adv
ersely affected by the phase fluctuations in the driving field. Furthe
r, there is a range of driving field detuning for which the refractive
index is considerably enhanced with vanishing absorption.