Active Bragg angle compensation for shaping ultrafast mid-infrared pulses

Active Bragg angle compensation is demonstrated for shaping ultrafast, mid-infrared pulses. The effects of angular dispersion introduced by the acousto-optic modulator on the temporal characteristics of the pulse are measured by autocorrelating the output from the pulse shaper. The time duration of the output pulses were measured to be thirty times shorter than pulses produced with a constant frequency amplitude waveform. This approach acts to mitigate angular dispersion in Bragg-regime acousto-optic devices, thus affording the ability to shape ultrafast pulses of light with broad bandwidths that are centered at mid-IR wavelengths and longer.