Propagation of optical pulses in a resonantly absorbing medium is studied. Propagation time of nanosecond pulses was measured for the Rb ${D}_{1}$ transition. At the center of two absorption lines, delay of the pulse peak which is about ten times as large as the pulse width was observed, where zero delay is defined for the propagation with the light velocity in vacuum. On the other hand, at the peak of an absorption line, negative delay was observed for large absorption, where the advance time is as large as 25% of the pulse width. Simulation including the effect of absorption and phase shift reproduced well the experimental results.Propagation of optical pulses in a resonantly absorbing medium is studied. Propagation time of nanosecond pulses was measured for the Rb ${D}_{1}$ transition. At the center of two absorption lines, delay of the pulse peak which is about ten times as large as the pulse width was observed, where zero delay is defined for the propagation with the light velocity in vacuum. On the other hand, at the peak of an absorption line, negative delay was observed for large absorption, where the advance time is as large as 25% of the pulse width. Simulation including the effect of absorption and phase shift reproduced well the experimental results.

Physical Review ANov 3, 200365 citations

Multiple scattering of light in a resonant medium

G. Labeyrie, Dominique Delande, Cord Axel Müller +2 more

Optics CommunicationsNov 4, 200434 citations

Diffuse Reflection and Transmission by Uniform Noncoherently Scattering Media

RBT Black

Diffusely reflected and transmitted spectral line profiles are calculated for uniform noncoherently scattering media onto which radiation of frequency near that of a resonance line of the medium is incident. Profiles are calculated for incident light that is either collimated or unifQrmly diffused and that is either monochromatic, or of uniform frequency distribution, or contains an absorption line centred on the resonance line under discussion. Spectral lines generated by uniformly excited media are also calculated.Diffusely reflected and transmitted spectral line profiles are calculated for uniform noncoherently scattering media onto which radiation of frequency near that of a resonance line of the medium is incident. Profiles are calculated for incident light that is either collimated or unifQrmly diffused and that is either monochromatic, or of uniform frequency distribution, or contains an absorption line centred on the resonance line under discussion. Spectral lines generated by uniformly excited media are also calculated.

Australian Journal of PhysicsJun 1, 19671 citation

Light interaction with resonance

Philippe Lalanne

May 18, 20160 citations

Effect of spontaneously generated coherence on absorption and dispersion in probe laser

Yan Xiang-An, Jianping Song, Bao-yin Yin +4 more

A theoretical investigation is carried into the effect of spontaneously generated coherence on absorption and dispersion in probe laser of Y-type atom system. It is found that the electromagnetically induce transparency window in the system narrows gradually as the spontaneously generated coherence intensifies. Moreover, the anomalous dispersion appears and the absorption changes from negative value to positive valve at resonance. At the same time, the absorption is zero or negative near resonance when the relative strength of the coupling field and pump field are different, and the atomic medium shows positive absorption when the two fields are exattly or nearly equal and close.A theoretical investigation is carried into the effect of spontaneously generated coherence on absorption and dispersion in probe laser of Y-type atom system. It is found that the electromagnetically induce transparency window in the system narrows gradually as the spontaneously generated coherence intensifies. Moreover, the anomalous dispersion appears and the absorption changes from negative value to positive valve at resonance. At the same time, the absorption is zero or negative near resonance when the relative strength of the coupling field and pump field are different, and the atomic medium shows positive absorption when the two fields are exattly or nearly equal and close.

Acta Physica SinicaJan 1, 200810 citations

Propagation of optical pulses in a resonantly absorbing medium is studied. Propagation time of nanosecond pulses was measured for the Rb

{D}_{1}

transition. At the center of two absorption lines, delay of the pulse peak which is about ten times as large as the pulse width was observed, where zero delay is defined for the propagation with the light velocity in vacuum. On the other hand, at the peak of an absorption line, negative delay was observed for large absorption, where the advance time is as large as 25% of the pulse width. Simulation including the effect of absorption and phase shift reproduced well the experimental results.