Showing papers on "Electromagnetically induced transparency published in 1995"
TL;DR: A theory of electromagnetically induced transparency in a three-level, ladder-type Doppler-broadened medium is developed, paying special attention to the case where the coupling and probe beams are counterpropagating and have similar frequencies, so as to reduce the total Dopplers width of the two-photon process.
Abstract: We develop a theory of electromagnetically induced transparency in a three-level, ladder-type Doppler-broadened medium, paying special attention to the case where the coupling and probe beams are counterpropagating and have similar frequencies, so as to reduce the total Doppler width of the two-photon process. The theory is easily generalized to deal with the \ensuremath{\Lambda} configuration, where the ideal arrangement involves two copropagating beams. We discuss different possible regimes, depending on the relative importance of the various broadening mechanisms, and identify ways to optimize the absorption-reduction effect. The theory is compared to the results of a recent experiment (on a ladder-type system), using the Rb D2 line, with generally very good agreement. The maximum absorption reduction observed (64.4%) appears to be mostly limited by the relatively large (\ensuremath{\sim}5 MHz) linewidth of the diode lasers used in our experiment.
563 citations
TL;DR: The first experimental studies of the temporal dynamics and spatial behavior of propagating EIT pulses are reported, including the observation of nearly diffractionlimited beam transmission in a medium which, without the coupling laser present, is nearly optically impenetrable.
Abstract: We describe the temporal and spatial dynamics of propagating electromagnetically induced transparency pulses in an optically thick medium. Results include pulse velocities as slow as $c/165$ with 55% transmission, strong-probe-field effects, and the observation of near diffraction-limited transmitted beam quality.
541 citations
TL;DR: A theoretical and experimental investigation has been carried out into the viability of V-type, ε-Lambda-type and cascade systems within rubidium for the observation of electromagnetically-induced transparency (EIT) as discussed by the authors.
Abstract: A theoretical and experimental investigation has been carried out into the viability of V-type, \ensuremath{\Lambda}-type, and cascade systems within rubidium for the observation of electromagnetically-induced transparency (EIT). A \ensuremath{\Lambda}-type system is also discussed where EIT is induced on a two-photon transition. Continuous-wave single-frequency titanium sapphire lasers have been employed to provide the applied optical fields. It is found that systems that have a strong coupling field resonant with the 5${\mathit{S}}_{1/2}$ ground state suffer from complicating optical pumping mechanisms that tend to mask EIT windows. It is also found that wavelength matching of the applied optical fields enhances the observation of EIT since this results in a reduced residual Doppler linewidth of the atomic system.
209 citations
TL;DR: In this paper, an electromagnetically induced transparency is observed at one arm of a three-level ε-Lambda-type system in a rubidium D1 line (794.8 nm) with an 85% reduction in absorption, when a pumping field is present at the other arm.
Abstract: An electromagnetically induced transparency is observed at one arm of a three-level \ensuremath{\Lambda}-type system in a rubidium D1 line (794.8 nm) with an 85% reduction in absorption, when a pumping field is present at the other arm. This reduction in absorption for the weak probe field is due to the atomic coherence produced by the strong pumping field. This experiment is done in a Rb vapor cell at room temperature with cw diode lasers for both pumping and probe beams in a Doppler-free configuration. A simple theoretical treatment including Doppler broadening is in good qualitative agreement with the experimental measurement.
175 citations
155 citations
99 citations
TL;DR: The transient behavior of an electromagnetically induced transparency in three-level atomic systems is described and Transient gain without population inversion and enhancement of dispersion are discussed.
Abstract: We describe the transient behavior of an electromagnetically induced transparency in three-level atomic systems. When the coupling f ield is switched on, the absorption for the probe field is oscillatorily damped to its new steady-state (transparent) value. Transient gain without population inversion and enhancement of dispersion are discussed. A realistic system for experimental testing of these effects is presented.
90 citations
TL;DR: In this paper, the authors discuss a requirement for the laser energy that is necessary to initiate electromagnetically induced transparency: the number of photons in the coupling laser pulse must exceed the product of the total number of atoms in the laser path times the ratio of the oscillator strengths of the probe and coupling laser transitions.
Abstract: We discuss a requirement for the laser energy that is necessary to initiate electromagnetically induced transparency: The number of photons in the coupling laser pulse must exceed the product of the number of atoms in the laser path times the ratio of the oscillator strengths of the probe and coupling laser transitions.
61 citations
TL;DR: A 64.4% reduction in absorption at the rubidium D2 line is observed when a pumping field at 775.8 nm is tuned on resonance to the transition between the excited states 5-5/2.
Abstract: A 64.4% reduction in absorption at the rubidium D2 line is observed when a pumping field at 775.8 nm is tuned on resonance to the transition between the excited states 5${\mathit{P}}_{3/2}$ and 5${\mathit{D}}_{5/2}$. As the pumping field is tuned off resonance, an absorption peak appears at the side of the Doppler-broadened D2 line. This modification in absorption is related to pumping-induced atomic coherence in this three-level ladder-type system. This experiment is done in a Rb vapor cell at room temperature and with cw diode lasers for both pumping and probe beams in a Doppler-free configuration.
51 citations
TL;DR: In this article, a cascade three-level EIT in rubidium vapour using continuous-wave titanium sapphire lasers is studied and the hyperfine structure of the upper level is seen within the EIT feature and the application of EIT to high resolution two-photon spectroscopy is discussed.
42 citations
TL;DR: In this paper, the hyperfine structures of highly-excited atomic states can be determined by electromagnetically-induced transparency experiment based on atomic coherence, and a theoretical model is presented and is in good agreement with the experimental results.
TL;DR: In this article, the effects of Zeeman splitting on electromagnetically-induced transparency in rubidium vapour has been carried out using two single-frequency, continuous-wave Ti:sapphire lasers.
TL;DR: Numerical calculations on the propagation of resonant optical pulse pairs in an absorbing medium of three-level Lambda systems are presented, finding that the NDD interactions reduce the effect of the electromagnetically induced transparency and the pulse group velocity.
Abstract: We present numerical calculations on the propagation of resonant optical pulse pairs in an absorbing medium of three-level \ensuremath{\Lambda} systems taking into account near dipole-dipole (NDD) interactions. We find that the NDD interactions reduce the effect of the electromagnetically induced transparency and the pulse group velocity. The NDD effect on phase modulation is also studied.
TL;DR: When two electron conduction subbands in a doped quantum well are coupled by a coherent laser pumping, electromagnetically induced transparency and Rabi splitting in the interband absorption spectrum of a probe light are found for steady electron dressed states.
Abstract: When two electron conduction subbands in a doped quantum well are coupled by a coherent laser pumping, electromagnetically induced transparency and Rabi splitting in the interband absorption spectrum of a probe light are found for steady electron dressed states. The effect of light-electron interaction on electron and hole eigenenergies and states are calculated using a generalized density-functional approach. The change of absorption coefficient with the pump field amplitude is studied and explained.
TL;DR: In this article, the steady state behavior of a Λ-type, three-level atomic system has been analyzed by taking into account the effect of the phase fluctuation, and it is shown that, even if the probe field is in resonance with the corresponding atomic transition, a large refraction index can still be generated; for a finite linewidth of the driving field, inversionless lasing and index enhancement tends to disappear.
Abstract: The steady-state behaviour for a Λ-type, three-level atomic system has been analysed by taking into account the effect of the phase fluctuation. It is shown that, for a monochromatic driving field, even if the probe field is in resonance with the corresponding atomic transition, a large refraction index can still be generated; for a finite linewidth of the driving field, inversionless lasing and index enhancement tends to disappear. Furthermore, the linewidth prevents the transparency of the medium.
TL;DR: In this article, the authors studied the evolution of a single mode of the quantized electromagnetic field interacting with both a collection of resonant two-level atoms and a Kerr medium, each of these interactions separately leads to a spreading of the initial field coherent states.
Abstract: We study the evolution of a single mode of the quantized electromagnetic field interacting with both a collection of resonant two-level atoms and a Kerr medium. Each of these interactions separately leads to a spreading of the initial field coherent states. Acting simultaneously, these two mechanisms of dispersion can cancel each other for special initial atomic states, allowing the propagation of field wave packets without spreading in the quantum phase space.
TL;DR: In this article, a new approach to the experimental search for P and T violating permanent electric dipole moments (EDMs) in atoms is proposed, where high dispersion of a phase coherent atomic medium at a point of electromagnetically induced transparency is used to detect linear Stark-shifts associated with an atomic EDM in a highly sensitive interferometric measurement.
Abstract: A new approach to the experimental search for P and T violating permanent electric dipole moments (EDMs) in atoms is proposed. The high dispersion of a phase coherent atomic medium at a point of electromagnetically induced transparency is used to detect linear Stark-shifts associated with an atomic EDM in a highly sensitive interferometric measurement. Possible noise sources are analysed and estimates are given for the device sensitivity.
TL;DR: In this paper, the Coulomb and field-induced electronic renormalization of the energy subbands and steady eigenstates of electrons were investigated in single and double quantum wells coupled by a resonant field.
Abstract: This paper presents the current results of field-induced quantum interference in semiconductor quantum wells. Three-level systems with two conduction subbands in single and double quantum wells coupled by a resonant field are studied. We investigate effects of the Coulomb and field-induced electronic renormalizations of the energy subbands and steady eigenstates of electrons. The random-phase and ladder approximations have been used to calculate the linear interband and intersubband optical absorptions and refractive indices. The effect of collective dipole moment on the nonlinear susceptibility has been incorporated into the study by using a local-field approach. Lasing without population inversion, electromagnetically induced transparency, and enhanced nonlinearity with reduced absorption inside the intersubband-coupled single quantum well and dc-field coupled double quantum wells are found.
TL;DR: In this paper, a density-matrix model which takes into account optical, Zeeman, and hyperfine coherences, and allows for a fluctuating laser field, correctly predicts the experimental observations.
Abstract: We present experimental and theoretical investigations of the ground-state levels of the Cs cycling transition. We show that in such multilevel nondegenerate systems, the populations of the extreme Zeeman sublevels, under optical pumping, can have asymmetric (``dispersive'') line shapes as a function of laser frequency. A density-matrix model which takes into account optical, Zeeman, and hyperfine coherences, and allows for a fluctuating laser field, correctly predicts the experimental observations. A comparison of the density-matrix model with a rate-equation model demonstrates the role of coherences in the population distribution. Investigation of the effect theoretically and experimentally for \ensuremath{\sigma} and \ensuremath{\pi} laser polarizations is presented in the paper.