Vector dynamics of pulsating solitons in an ultrafast fiber laser.

We experimentally investigate the vector nature of various pulsating solitons in an ultrafast fiber laser with single-wall carbon nanotubes. By virtue of the dispersive Fourier transform technique, the polarization-resolved spectral evolution of pulsating vector solitons is measured in real time. In the case of single-periodic pulsation, pulsating behaviors of the two orthogonal polarization components can be either synchronous or asynchronous. We also observe double-periodic pulsation in the cavity for the first time, to the best of our knowledge. It is shown that the shot-to-shot spectra oscillate with two combined modulation periods involved in this process. Our results would be beneficial for further understanding of the vector dynamics of pulsating solitons in dissipative systems.