Depolarized source for fiber-optic applications.

Two diode-pumped Nd:YAG lasers are combined with their polarization vectors at 90° to each other to create a depolarized source suitable for propagation over long lengths of ordinary, low-birefringence single-mode fiber without a change in the polarization state. The source is demonstrated with an integrated-optical Mach–Zehnder interferometer and provides a constant −3-dB intensity input to the required linear input polarization state.