Numerical modeling of evolution of nano- and picosecond probe pulses of electromagnetically induced transparency

Abstract

Results of numerical analysis of the influence of probe pulse duration on the character of its evolution under the conditions of electromagnetically induced transparency in a Λ-scheme involving degenerate quantum transitions are presented. The cases of weak and strong input probe pulses linearly polarized in the same direction as the polarized coupling radiation, along with the case of linearly polarized probe radiation and circularly polarized coupling radiation, are considered. Calculations showed that the regime of weak probe radiation is most favorable for formation of a short probe pulse with a duration of about 1 ns and pulse shape that does not change substantially upon pulse propagation. However, even in this case, picosecond probe pulses experience considerable deformation of their shape and loss of power. Considerable changes of the pulse shape in the case of a strong probe pulse occur already when the pulse duration approaches 1 ns. This circumstance can limit the response time of prospective devices based on the effect of electromagnetically induced transparency.