Optical delay with spectral hole burning in Doppler broadened cesium vapor

The full frequency dependence of the optical delay in the Cs D1 (6 2S1/2−6 2P1/2) line has been observed, including all four hyperfine split components. Pulse delays of 1.6ns to 24.1ns are obtained by scanning across the hyperfine splitting associated with the lower 2S1/2 state. Optical control of pulse delays in cesium vapor was demonstrated by pumping the D2 (6 2S1/2−6 2P3/2) transition and observing resulting holes in the D1 delay spectrum. For a pump at four times the saturation intensity, the pulse delays are reduced by a maximum of 78% in a narrow region of 110MHz. The frequency dependence of the delays of the probe laser in the vicinity of the spectral holes agrees with a Kramers–Kronig model prediction