Polarization-independent double phase conjugate mirror

We present a polarization-independent double phase conjugate mirror (DPCM) working at telecommunication wavelength 1.32 mu m. To do this, InP:Fe photo refractive crystals are used. A 2Z-DPCM configuration is realized in order to eliminate conical diffraction and to reduce the instabilities. With this device, the conjugation efficiency remains almost unchanged when the polar ization state of the incident beam varies. Dynamic measurements demonstrate that the device is well-adapted to relatively slow variations of the polar ization, induced by thermal variations for example. (C) 1999 Elsevier Scien ce B.V. All rights reserved.