Optical trap potential control in N-type four level atoms by femtosecond Gaussian pulses

TL;DR

This paper demonstrates how femtosecond Gaussian pulses can be used to precisely control the optical trap potential in a four-level atomic system, with trap size and splitting behavior adjustable via pulse parameters.

Contribution

It introduces a novel scheme for controlling optical trap potentials in N-type four-level atoms using chirped femtosecond pulses, including analysis of trap splitting phenomena.

Findings

Trap size controlled by beam waist and detuning.

Trap potential splits with increasing Rabi frequency.

Behavior analogous to nanoparticle trapping with femtosecond pulses.

Abstract

In this work we present a scheme to control the optical dipole trap potential in an N-type four-level atomic system by using chirped femtosecond Gaussian pulses. The spatial size of the trap can be well controlled by tuning the beam waist of the Gaussian pulse and the detuning frequency. The trapping potential splits with increasing Rabi frequency about the center of the trap, a behavior analogous to the one observed experimentally in the context of trapping of nanoparticles with femtosecond pulses. An attempt is made to explain the physics behind this phenomenon by studying the spatial probability distribution of the atomic populations.