Pulse-splitting in light propagation through $N$-type atomic media due to an interplay of Kerr-nonlinearity and group velocity dispersion

TL;DR

This paper studies how Gaussian light pulses split into multiple subpulses when passing through an N-type atomic medium, due to Kerr nonlinearity and dispersion, with controllable parameters affecting the splitting.

Contribution

It demonstrates the controlled pulse splitting phenomenon in N-type media caused by nonlinear and dispersive effects, supported by a theoretical model.

Findings

Pulse splitting depends on probe pulse intensity.

Number of subpulses can be controlled via field parameters.

Splitting results from Kerr nonlinearity and group velocity dispersion.

Abstract

We investigate the spatio-temporal evolution of a Gaussian probe pulse propagating through a four-level $N$-type atomic medium. At two-photon resonance of probe-and control fields, weaker probe pulses may propagate through the medium with low absorption and pulse shape distortion. In contrast, we find that increasing the probe pulse intensity leads to a splitting of the initially Gaussian pulse into a sequence of subpulses in the time domain. The number of subpulses arising throughout the propagation can be controlled via a suitable choice of the probe and control field parameters. Employing a simple theoretical model for the nonlinear pulse propagation, we conclude that the splitting occurs due to an interplay of Kerr nonlinearity and group velocity dispersion.