Polarization-gating frequency-resolved optical gating
= Polarization-gating frequency-resolved optical gating
{title2=$A_{\rm sig}(t,\tau)\propto A(t)|A(t-\tau)|^2$}
An optical Kerr gate rotates a probe's polarization in proportion to a delayed replica's <intensity> in the weak-gate regime. Resolving the gated spectrum gives a pulse-characterization record with a third-order gate law, distinct from a second-harmonic gate.