All-Fiber Source of Polarization-Entangled Photon Pairs Based on a Novel   Birefringence Compensated Scheme
  We propose a new all-fiber source of polarization-entangled photon pairs for quantum communications. Fiber birefringence is compensated using Faraday rotator mirror, resulting in enhanced stability against random polarization drifts compared to existing schemes. 
Han Chuen Lim, Dexiang Wang, Takuo Tanemura, Kazuhiro Katoh, Kazuro   Kikuchi