Observation of Polarization-Locked Vector Solitons in an Optical Fiber

Abstract

We observe polarization-locked vector solitons in a mode-locked fiber laser. Temporal vector solitons have components along both birefringent axes. Despite different phase velocities due to linear birefringence, the relative phase of the components is locked at $\ifmmode\pm\else\textpm\fi{}\ensuremath{\pi}/2$. The value of $\ifmmode\pm\else\textpm\fi{}\ensuremath{\pi}/2$ and component magnitudes agree with a simple analysis of the Kerr nonlinearity. These fragile phase-locked vector solitons have been the subject of much theoretical conjecture, but have previously eluded experimental observation.