Eur. Phys. J. D (2012) 66: 317
https://doi.org/10.1140/epjd/e2012-30248-4

Regular Article

Phase dependent effect on the resonant absorption spectrum in a Ξ-configuration atom driven by a pair of bichromatic fields

¹ Department of Physics, Northwest University, Xi’an 710069, P.R. China
² National photoelectric technology and Functional Materials and Application of Science and Technology International Cooperation Base, Xi’an 710069, P.R. China
³ National Key Laboratory of photoelectric technology and Functional materials (Culture Base), Xi’an 710069, P.R. China
⁴ Institute of Modern Physics, Northwest University, Xi’an 710069, P.R. China

^a e-mail: jinkang@nwu.edu.cn
^b e-mail: xtxie@nwu.edu.cn

Received: 17 April 2012
Received in final form: 24 August 2012
Published online: 21 December 2012

Abstract

The absorption spectrum of the upper transition in a Ξ-configuration three-level atomic system driven by a pair of bichromatic fields is studied. The spectrum exhibits a multipeaked absorption spectrum with a constant peak separation depending on the detuning of the driving field. We find the resonant absorption is suppressed continuously with the increase of the detuning. As a result, for a sufficiently large detuning, the frequency range between inner sidepeaks form an approximately transparent window of which the width can be controlled through adjusting the field detuning. Additionally, we find that the comb-like absorptive spectrum can be turned into an comb-like emissive spectrum when the modulation of phases of the driving fields is involved. The main results are interpreted in term of the dressed-state formalism.