Low-Speed and Suspended Propagation of Light Pulses in Atomic Medium with Electromagnetically Induced Transparency

Experiments on hot rubidium vapor as an atomic medium with electromagnetically induced transparency for radiation of 795 nm wavelength (D1 absorption line of rubidium) are reported. Propagation of light pulses with velocity reduced to 11.5 km/s has been observed with a significant modification of the shape of square input pulses to adapt to the spectral window of induced transparency. So-called light storage, i.e. suspension of the propagation of light pulses in the medium by temporary turn-off of the electromagnetically induced transparency state was also demonstrated. “Storage” periods of several microseconds, limited by relatively fast relaxation of atomic spin polarization in the volume of interaction of atoms with radiation, were obtained.