Simultaneous quantum state measurements using array detection

A.M. Dawes and M. Beck, Physical Review A **63**, 040101 (R), (2001) (4 pages).

__Abstract__

We have simultaneously measured the quantum states of two different spatial
modes of the same optical beam by performing quantum state tomography with an
array detector. Both modes are well
described by coherent states, but the projection of the signal onto the local
oscillator mode contains a mean of 0.09 photons, while a more complicated mode
has a mean of 4.3 photons. This
demonstrates that for this particular mode the effective detection efficiency
when using array detection is over 40 times greater than when using single
detectors.