Low group velocity of light without an extra driving laser field

摘要

Coherent light pulse propagation is investigated in a medium of three-level atoms with two possibly closely spaced upper levels without the presence of any auxiliary driving laser fields. We derive an analytic expression for the group velocity in this system and demonstrate that it may be very low along with a small pulse distortion for a certain range of intensities. The group velocity is shown to depend sensitively on the upper level splitting and may thus be conveniently controlled by a magnetic field rather than an extra laser field. (C) 2003 Elsevier Science B.V. All rights reserved. [References: 15]