Real‐time optical waveform convolver/cross correlator

We show that an inhomogeneously broadened sample, excited by a series of three resonant optical pulses, emits an optical signal whose electric field envelope closely approximates the convolution or cross correlation of the field envelopes belonging to two of the three excitation pulses. The convolution (cross correlation) function is obtained when the first (second) pulse in the excitation sequence is short compared to the temporal structure of the other two excitation pulses.