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arXiv:1705.10752 · Journal of Physics B Atomic Molecular and Optical Physics

Population trapping in the excited states using vacuum-induced coherence and adiabatic process

Babu Lal Kumawat, Pardeep Kumar, Shubhrangshu Dasgupta

Published Jan 26, 2018• 1 citation
arXivHTMLPDF

Abstract

Abstract We theoretically investigate how population can be trapped in the closely spaced excited levels in presence of vacuum-induced coherence (VIC). We employ delayed pulses to transfer population from a meta-stable state to the excited states. Subsequently, spontaneous emission from these excited states builds coherence between them. This coherence can be probed by using chirping, which leads to the decoupling of the excited states from the ground state thereby ensuring population transfer via delayed pulses. Our results indicate that the existence of VIC leads to the generation of a mixed state in the excited state manifold, where trapping of the population occurs even in the presence of large decay. This trapping may be realized in molecular systems and can be interpreted as a sensitive probe of VIC. We present suitable numerical analysis to support our results.

DOI
10.1088/1361-6455/aaa69d

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