Abstract

Two-wave mixing in photorefractive media removes mechanical vibrations and laser speckle during laser-based ultrasound detection. We demonstrate that photorefractive quantum wells always provide the condition for maximum linear homodyne sensitivity (also known as quadrature) because of the resonant dielectric response of the quantum-confined excitons. The dispersion of the excitonic absorption provides an excitonic spectral phase that is directly accessible by tuning the detection wavelength.

© 1999 Optical Society of America