Pulsed Squeezed Light

Squeezed light in the form of a train of pulses, each approximately 100 ps in width, has been generated by parametric down-conversion in KTiOP${\mathrm{O}}_4$ crystals. The measured noise reduction in the quiet quadrature of the field is 0.6 dB below the shot-noise limit. The quadrature noise components are measured with a balanced homodyne detector using a pulse train for the local oscillator. The noise reduction extends over a broad spectrum and has important implications for precision measurement at very short time scales.