Abstract

All-optical regeneration^1,2 and demultiplexing^3,4 in a nonlinear optical-loop mirror (NOLM) have been demonstrated. We propose a polarization-independent regenerator including erbium-doped fiber amplifiers (EDFAs) and an optical clock-recovery and decision circuit. The latter is a NOLM (NOLM2 in Fig. 1) in which accurately timed clock pulses (wavelength λ,) act as a signal, while optically amplified received modulated return-tb-zero (RZ) pulses (wavelength λ,) act as a cross-phasemodulation pump.^1,2 A signal-polarization-independent NOLM contains a section of dispersion-shifted polarization-maintaining fiber (PMF) that is subdivided into two 0°- and 90°-oriented PM F pieces for polarization walk-off compensation⁵ (NOLM 1).

© 1994 Optical Society of America