相关论文: Phase-controlled transparent superluminal light pr…
We investigate the behavior of fast light pulse propagation in an N-type Doppler-broadened 4-level atomic system using double Raman gain processes. This system displays novel and interesting results of two controllable pairs of the double…
We investigate the dispersion and the absorption properties of a weak probe field in a three-level Lambda-type atomic system. We use just an incoherent field for controlling the group velocity of light. It is shown that the slope of…
The propagation of light-pulse with negative group-velocity in a nonlinear medium is studied theoretically. We show that the necessary conditions for these effects to be observable are realized in a three-level $\Lambda$-system interacting…
In recent years, control of group velocity of light has attracted enormous interest. One of the main challenges is to realize an absorption-free fast or slow light propagation. Here, we study dispersion and absorption properties of a weak…
The sub-luminal phase velocity of electromagnetic waves in free space is generally unobtainable, being closely linked to forbidden faster than light group velocities. The requirement of effective sub-luminal phase-velocity in laser-driven…
The propagation of a weak probe field in a laser-driven four-level atomic system is investigated. We choose mercury as our model system, where the probe transition is in the ultraviolet region. A high-resolution peak appears in the optical…
Dispersion and absorption properties of a weak probe field in a three-level V-type atomic system is studied. By application of indirect incoherent pump fields the effect of populating upper levels on optical properties of the atomic medium…
We investigate the dispersion and the absorption properties of a weak probe field in a three-level pump-probe atomic system. It is shown that the slope of dispersion changes from positive to negative just with the intensity of the coherent…
Nonlinear effects in pulse propagation through a medium consisting of four-level double-$\Lambda$-type systems are studied theoretically. We apply three continous-wave driving fields and a pulsed probe field such that they form a closed…
We investigate dispersion and absorption properties of a weak probe field in a four level atomic system through interacting dark resonances. We show that two narrow peaks appears in the optical spectra due to the presence of interacting…
The light propagation of a probe field pulse in a four-level double-lambda type system driven by laser fields that form a closed interaction loop is studied. Due to the finite frequency width of the probe pulse, a time-independent analysis…
We show how the application of a coupling field connecting the two lower metastable states of a lambda-system can produce a variety of new results on the propagation of a weak electromagnetic pulse. In principle the light propagation can be…
We investigate the spatio-temporal evolution of a Gaussian probe pulse propagating through a four-level $N$-type atomic medium. At two-photon resonance of probe-and control fields, weaker probe pulses may propagate through the medium with…
The propagation of a probe laser field in a cavity optomechanical system with a Bose-Einstein condensate is studied. The transmission properties of the system are investigated and it is shown that the group velocity of the probe pulse field…
The mechanisms leading to a seemingly superluminal propagation of light in dispersive media are examined. The anomalous dispersion near an absorption line, involved in the first experiments displaying negative group velocity propagation, is…
We study the change of the probe field group velocity from subluminal to superluminal range for two kinds of closed three-level V-type system with spontaneously generated coherence and incoherent pumping field. For the first kind of the…
We examine the propagation of a weak probe light through a coherently driven $Y$-type system. Under the condition that the excited atomic levels decay via same vacuum modes, the effects of quantum interference in decay channels are…
The propagation of a weak optical pulse through an atomic system in closed $\Lambda$ configuration is investigated in which the hyper fine levels are coupled by a microwave pulse. Under three photon resonance condition, it is observed that…
We investigate the dynamics of a pair of short laser pulse trains propagating in a medium consisting of three-level $\Lambda$-type atoms by numerically solving the Maxwell-Schr\"odinger equations for atoms and fields. By performing…
We present a theoretical analysis of the propagation of light pulses through a medium of four-level atoms, with two strong pump fields and a weak signal field in an N-scheme arrangement. We show that the generation of four-wave mixing has a…