Ultrafast polarization dynamics and noise in pulsed vertical-cavity surface-emitting lasers

We have measured on ps time scales the temporal behavior of the intensity n oise of, and correlations between, orthogonally polarized modes in an optic ally pumped VCSEL. Measurements were made in both the circular and the line ar bases. Sub-ps optical pumping with circular polarization leads to positi vely correlated intensity noise for emission in orthogonal linear polarizat ions. Optical pumping with linear polarization leads to anti-correlated int ensity noise for emission in orthogonal linear polarizations, due to random orientation of linearly polarized emission. Intensity noise for circularly polarized emission is uncorrelated or anti-correlated depending on spin-fl ip rates which determine the strength of gain competition. We have generali zed the theoretical treatment of San Miguel, Feng, and Moloney to successfu lly model these phenomena. (C) 2001 Optical Society of America.