Squeezed light from injection-locked quantum well lasers

Abstract

Measurements based on balanced detection demonstrate more than 3 dB photon-number squeezing from a quantum well laser injection locked to a coherent signal. We show that injection locking significantly reduces the photon-number fluctuation by suppressing weak side modes that feature intensity noise far above the standard quantum limit. The measurements also reveal that the photon statistics vary qualitatively with the polarization of the laser field.