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AIP conference proceedings

Coherent population transfer and optical dipole force by chirped Gaussian femtosecond pulses in four level 87Rb

Subhadeep Chakraborty, Amarendra K. Sarma

Published Jan 1, 2014• 0 citations
Publisher

Abstract

We report coherent population transfer(CPT) in a four level atomic system, coupled by three chirped Gaussian femtosecond pulses. CPT is studied under two specific conditions beyond the RWA. It is observed that nearly complete population transfer to the states |3> and |4> can be achieved by maintaining proper resonance condition and judiciously choosing the laser parameters. In addition to this, the transverse optical dipole force on the four-level atomic system is numerically studied. The transverse force provides an acceleration to an atom which is eight order of magnitude higher than earth’s gravitational acceleration g. The force changes from a focusing force to a defocusing one as the initial population changes from the ground states to the excited states.

DOI
10.1063/1.4898295

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