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 1.6 ns to 24.1 ns 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 110 MHz. The frequency dependence of the delays of the probe laser in the vicinity of the spectral holes agrees with a Kramers-Kronig model prediction.