Measuring Photon Antibunching from Continuous Variable Sideband Squeezing

We present a technique for measuring the second-order coherence function g⁽²⁾(τ) of light using a Hanbury Brown Twiss intensity interferometer modified for homodyne detection. The experiment was performed entirely in the continuous-variable regime at the sideband frequency of a bright carrier field. We used the setup to characterize g⁽²⁾(τ) for thermal and coherent states and investigated its immunity to optical loss. We measured g⁽²⁾(τ) of a displaced-squeezed state and found a best antibunching statistic of g⁽²⁾(0)=0.11±0.18.