Polarization preserving ultra fast optical shutter for quantum   information processing
  We present the realization of a ultra fast shutter for optical fields, which allows to preserve a generic polarization state, based on a self-stabilized interferometer. It exhibits high (or low) transmittivity when turned on (or inactive), while the fidelity of the polarization state is high. The shutter is realized through two beam displacing prisms and a longitudinal Pockels cell. This can represent a useful tool for controlling light-atom interfaces in quantum information processing. 
Nicolo' Spagnolo, Chiara Vitelli, Sandro Giacomini, Fabio Sciarrino   and Francesco De Martini