Joint quantum measurement using unbalanced array detection

Andrew M. C. Dawes, M. Beck

Andrew M. C. Dawes, M. Beck

M. Beck, Christophe Dorrer, Ian A. Walmsley

We have measured the joint Q-function of a highly multimode field using unbalanced heterodyne detection with a charge-coupled device array detector. We use spectral interferometry between a weak signal field and a strong, 100 fs duration local oscillator pulse to reconstruct the joint quadrature amplitude statistics of about 25 temporal modes. By adjusting the time delay between the signal and local oscillator pulses we are able to shift all the classical noise to modes distinct from the signal. This obviates the need to use a balanced detector.

M. Beck, Christophe Dorrer, Ian A. Walmsley

We have measured the joint Q-function of a highly multimode field using unbalanced spectral heterodyne detection with a charge-coupled device array. We reconstruct the statistics of about 25 adjacent temporal modes each of about 100 fs duration.

Brandon S. Harms, Blake E. Anthony, Noah T. Holte +2 more

We measure the joint $Q$ function of a multispatial-mode field using a charge-coupled device array detector in an unbalanced heterodyne configuration. The intensity pattern formed by interference between a weak signal field and a strong local oscillator is resolved using Fourier analysis and used to reconstruct quadrature amplitude statistics for 22 spatial modes simultaneously. The local oscillator and signal propagate at an angle of $12\phantom{\rule{0.28em}{0ex}}\mathrm{mrad}$, thus shifting the classical noise to modes that do not overlap with the signal. In this configuration, balanced detection is not necessary.

M. Beck, Christophe Dorrer, Ian A. Walmsley