Original scientific paper
Coherent control of spontaneous emission spectrum in a doubly driven Y-type atom
Bibhas Kumar Dutta
; Department of Physics, J. K. College, Purulia 723 101, India
Prasanta Kumar Mahapatra
; Department of Physics and Technophysics, Vidyasagar University, Midnapore 721 102, India
Abstract
We have studied the dynamic control of the spontaneous emission spectrum in a Y-type atomic system driven by two coherent fields. In different dynamic conditions, the evolution of coherent spectral features in the bare-state model, has been analyzed by using the dressed-state model. For the system under purely dissipative environment, it has been shown that the behaviour of spectral components can be coherently controlled by changing the values of the Rabi frequencies and detunings of external fields. At the condition of resonant evolution of spectra, present work highlights that the emission line shape can be strongly modified for unequal decay rates of the uppermost doublet states. In this situation, the phenomenon of constructive quantum interference gives rise to the emergence of a single peak at a certain spectral position when two distinct peaks disappear at the other spectral positions. Owing to the mutual orientation of polarizations of the fields interacting with the atom in a specific configuration, we have incorporated the static phase-variation effect to exhibit phase-dependent spectra. We consider the present model with a typical field configuration such that the frequency mismatch between two coherent fields introduces the dynamic phase-variation effect. This phenomenon leads to obtain anomalous peak-shifting effect accompanied by the selective quenching of emission within the spectral profile.
Keywords
doubly driven Y-type atom; dynamic control of coherent spectral features; incoherent elimination of spectral component; dependence of the line intensity on the incoherent pumping rate; static and dynamic phase-variation effects; phase-dependent emission spectra; anomalous peak shifting effect
Hrčak ID:
302803
URI
Publication date:
1.9.2010.
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