Single-shot supercontinuum spectral interferometry

We have developed a single-shot spectral interferometer using the supercontinuum pulse generated by self-focusing in atmospheric pressure air. The diagnostic can be used to measure ultrafast refractive index transients either in a direct frequency-to-time mapping mode or in a full Fourier transform mode. In the direct mapping mode, temporal resolution is shown to be strongly restricted by the pulse chirp. In the transform mode, the ultimate temporal resolution is limited by the supercontinuum pulse bandwidth and the maximum pump-induced phase shift.