Polarization switching (PS) between two orthogonal linearly polarized fundamental modes is experimentally observed in commercial free-running 1550 nm vertical-cavity surface-emitting lasers (VCSELs) (Raycan). The characteristics of this PS are strongly modified after introducing a polarization-preserved (PP) or polarization-orthogonal (PO) optical feedback. Under the case that the external cavity is approximately 30 cm, the PP optical feedback results in the PS point shifting toward a lower injection current, and the region within which the two polarization modes coexist is enlarged with the increase of the PP feedback strength. Under too-strong PP feedback levels, the PS disappears. The impact of PO optical feedback on VCSEL polarization behavior is quite similar to that of PP optical feedback, but larger feedback strength is needed to obtain similar results.
© 2013 Optical Society of America
Lasers and Laser Optics
Original Manuscript: March 15, 2013
Revised Manuscript: April 24, 2013
Manuscript Accepted: April 26, 2013
Published: May 30, 2013
Tao Deng, Zheng-Mao Wu, Yi-Yuan Xie, Jia-Gui Wu, Xi Tang, Li Fan, Krassimir Panajotov, and Guang-Qiong Xia, "Impact of optical feedback on current-induced polarization behavior of 1550 nm vertical-cavity surface-emitting lasers," Appl. Opt. 52, 3833-3837 (2013)