Two-photon absorption in strong fields

H. Bovensmann, E. Tiemann

A. Chakraborty, Satya Ram Mishra

Stephen V. Kershaw

Bang‐Pin Hou, Shun-Jin Wang, W L Yu +1 more

We consider the one- and two-photon absorption spectra of a four-level Y-type atom with the two highest lying levels driven by a microwave field. We found that in the one-photon absorption case, the microwave field can lead to the probe gain, and the absorption and gain spectral structures depend strongly on the microwave field amplitude. For the two-photon absorption case, the strong microwave field can enhance the absorption. When the microwave field amplitude is reduced to a certain value, the single absorption peak in the two-photon spectrum changes into a structure of two-peak structure with different magnitudes. Moreover, the one- and two-photon absorption spectra can be modulated by the phase of the microwave field which produces a closed-loop configuration. Finally, we use the analytic solutions in terms of dressed-state basis to explain the results from our numerical calculation.

清 西川, 昭 佐道, Hiroshi Sekiya +3 more

Seyyed Hossein Asadpour, HAMID RAHIMPOUR SOLEIMANI

In this paper, the effect of microwave field on the transient and steady state response of the four-level inverted Y-type atomic system is investigated. It is found that the properties of transient and steady processes can be affected by microwave field. It is found that the absorption spectrum behaves differentially for single-photon absorption and two-photon absorption. Also it is observed that in the one-photon absorption, the microwave field can lead to the probe gain and for two-photon absorption case, the strong microwave can enhance the absorption.