Physical Review A

Autler-Townes effect with mono- and bichromatic pump fields: Reservoir effects and Floquet-state treatment

Matthias Jakob, Gagik Yu. Kryuchkyan

Published Feb 1, 1998• 31 citations

Abstract

The probe-field absorption spectra are investigated for three-level atoms interacting with mono- or bichromatic fields in the presence of bath reservoirs of different kinds. Two configurations of atoms with lower-level and upper-level couplings are considered on the basis of Floquet-state dynamics. The multipeak Autler-Townes splitting induced by the resonant interaction of atoms with bichromatic fields is investigated and driving-field effects as well as squeezed-bath effects on the absorption spectra are analyzed. Ultrasharp absorption lines can be obtained in the upper-level coupling scheme due to a mixing of two atomic decay channels by the bichromatic field.

DOI: 10.1103/physreva.57.1355

Related papers

Autler-Townes effect for an atom in a 100% amplitude-modulated laser field. II. Experimental results

Stephanos Papademetriou, Michael F. Van Leeuwen, Carlos R. Stroud

We report the observation of the Autler-Townes absorption spectrum of a two-level atom in a 100% amplitude-modulated optical field. Two frequency-stabilized dye lasers interact with a three-level atomic cascade system. One of the two lasers is used to create the bichromatic field that saturates the lower transition, while the second one is tuned in the frequency between the second and third levels to probe the absorption line shape. We investigate the dependence of the spectrum on the detuning between the average frequency of the bichromatic field and the lower atomic resonance. In order to study the effects of saturation, for every value of the detuning we take a series of data for different intensity levels of the bichromatic field. There is very good agreement between theory and experiment and profound differences from the conventional Autler-Townes results with a monochromatic pump field. \textcopyright{} 1996 The American Physical Society.

Physical Review AFeb 1, 199642 citations

Amplitude-modulated optical double resonance

van K.A.H. Leeuwen, Michael Francis

We have investigated the interaction between bichromatic optical fields and atomic transitions. We have considered both the interaction of a saturating bichromatic field in the form of a 100% amplitude-modulated field resonantly interacting with a single atomic transition as well as the interaction of a pair of 100% amplitude-modulated fields with two coupled atomic transitions. In our studies of a single atomic transition resonantly excited by a 100% amplitude-modulated field we have used a fully quantum-electrodynamical analysis to model the Autler-Townes effect induced by a bichromatic optical field. We find that the effect induced by a bichromatic field is markedly different from the effect produced by a monochromatic exciting field. We have derived analytic expressions for the bichromatic Autler-Townes absorption spectrum. The absorption spectrum consists of equally spaced lines spaced by the modulation frequency. The linewidths of neighboring lines alternate as functions of the field strength. Experimentally, we observed this spectrum for both resonant and detuned 100% amplitude-modulated driving fields by monitoring the absorption of a weak monochromatic field as it was tuned about the resonance frequency of the 3²P₃/₂(F = 3, mF = 3) ↔ 4²D₅/₂(F = 4, mF = 4) transition while driving the 3²S₁/₂(F = 2, mF = 2) ↔ 3²P₃/₂(F = 3, mF = 3) transition with a saturating 100% amplitude-modulated field. We found excellent agreement between our predicted and measured spectra. We then investigated the resonant interaction between a pair of 100% amplitude-modulated fields and two atomic transitions sharing a common atomic level. We considered both a three-level atomic cascade system and a three-level atomic lambda system. We examined the effect that the relative phase between the two modulations has on the rate at which the modulated fields are absorbed. We find that the saturated time-averaged field absorption exhibits parametric resonances in both the cascade and lambda systems. The time-averaged absorption is strongly dependent upon the relative phase of modulation between the two fields and for certain phase differences the time-averaged absorption can be enhanced over the maximum saturated absorption experienced by cw fields of the same time-averaged intensities. We also find that the stationary atomic response exhibits periodic oscillations and for the cascade system periodic two-photon inversions of up to 40% can be achieved. We further find dark absorption resonances as a function of phase in the lambda system. We analyze the results from the point of view of semi-classical adiabatic dressed states.

Jan 1, 19980 citations

Autler-Townes absorption spectrum of a bichromatic field

Stephanos Papademetriou, Michael F. Van Leeuwen, Carlos R. Stroud

The interaction of a strong bichromatic field with a two-level atom has been the subject of numerous experimental and theoretical investigations, but some outstanding questions remain concerning the widths of the various lines in the spectra.

Annual Meeting Optical Society of AmericaJan 1, 19930 citations

Autler-Townes effect for an atom in a 100% amplitude-modulated laser field. I. A dressed-atom approach

Michael F. Van Leeuwen, Stephanos Papademetriou, Carlos R. Stroud

A dressed-state rate-equation model is used to describe the Autler-Townes effect that is produced by a resonant 100% amplitude-modulated field driving a two-level resonance. The purpose of using this model is to give an intuitive interpretation of the rather complex absorption spectra that are produced when a weak probe field couples this strongly driven transition to a third atomic state. We obtain analytic expressions for the positions, strengths, and widths of the components of the absorption spectra, which are in excellent agreement with experimentally obtained spectra presented in the accompanying paper [S. Papademetriou, following paper, Phys. Rev. A 53, 997 (1996)]. \textcopyright{} 1996 The American Physical Society.

Physical Review AFeb 1, 199631 citations

Electromagnetically induced transparency and Autler-Townes splitting: Two similar but distinct phenomena in two categories of three-level atomic systems

Tony Abi-Salloum

Electromagnetically induced transparency (EIT) and Autler-Townes (AT) splitting are two phenomena that could be featured in a variety of three-level atomic systems. The considered phenomena, EIT and AT, are similar ``looking'' in the sense that they are both characterized by a reduction in absorption of a weak field in the presence of a stronger field. In this paper, we explicitly set the threshold of separation between EIT and AT splitting in a unified study of four different three-level atomic systems. Two resonances are studied and compared in each case. A comparison of the magnitudes of the resonances reveals two coupling-field regimes and two categories of three-level system.

Physical Review AMay 19, 2010159 citations

Dynamical suppression of the Autler-Townes doublet in the presence of a cavity

Peng Zhou, S. Swain

We study the Autler-Townes absorption spectrum of the upper and intermediate levels of a three-level cascade atom in which the intermediate and ground levels are strongly driven by a laser field as well as weakly coupled by a cavity mode [Phys. Rev. 100, 703 (1955)]. Surprisingly, one of the Autler-Townes peaks may be greatly suppressed or enhanced by tuning the cavity resonant frequency. The larger the Rabi frequency, the more pronounced the cavity-induced suppression or enhancement. The Autler-Townes spectrum carries full information on the cavity-induced modification of the strongly driven levels. A physical interpretation is presented in the dressed-state basis.

Physical Review AMay 1, 19985 citations