Shape preserving atomic pulse amplifier

TL;DR

This paper demonstrates a method for amplifying weak probe pulses in a resonant atomic system that preserves the pulse shape and stability, enabling distortion-free propagation at the speed of light.

Contribution

It introduces a control field technique that amplifies and preserves the shape of arbitrary probe pulses in a $ ext{Lambda}$ system without delay or distortion.

Findings

Probe pulse is amplified without distortion.

Pulse propagates at light speed post-amplification.

Technique works for arbitrary pulse shapes.

Abstract

Propagation of a weak probe pulse through a $\Lambda$ system in a resonant gain configuration is investigated. We employ the control field intensity that permits the amplification of probe pulse during propagation, without instability at two photon resonance. Posterior to amplification, a broadened probe pulse is obtained, which retains its initial pulse shape and travels at the speed of light in vacuum, without experiencing any delay, absorption, and dispersion. The salient feature of this technique lies in the fact that in addition to preserving the initial pulse shape, it also ensures stable pulse propagation after amplification. It also works for arbitrary probe pulse shapes.