New Photodetection Method Using Unbalanced Sidebands for Squeezed   Quantum Noise in Gravitational Wave Interferometer
  Homodyne detection is one of the ways to circumvent the standard quantum limit for a gravitational wave detector. In this paper it will be shown that the same quantum-non-demolition effect using homodyne detection can be realized by heterodyne detection with unbalanced RF sidebands. Furthermore, a broadband quantum-non-demolition readout scheme can also be realized by the unbalanced sideband detection. 
K. Somiya