Coherent nonlinear optical spectroscopy using photon-number squeezed light

Abstract

Using coherent nonlinear optical spectroscopy below the band edge of a GaAs/${\mathrm{Al}}_{0.3}$ ${\mathrm{Ga}}_{1-0.3}$As multiple quantum well, photon-number squeezed light generated by a quantum-well laser is used to resolve the exciton resonances and the Urbach tail with detection sensitivity below the semiclassical shot-noise limit. The effect of polarization-dependent noise in the nonclassical probe field is also investigated.