The polarization-dependent gain (PDG) characteristics of a vertical-cavity semiconductor optical amplifier (VCSOA) are measured, and the case of the PDG is determined. It is often assumed that the polarization states of a VCSOA are degenerate because of the circular geometry of the device. This assumption is not true in practice, and it is found that VCSOAs possess a dominant linear polarization state and a small difference in frequency between polarization states. The difference in resonant frequencies causes the PDG of the VCSOA. Measurements of the polarization state show that the cause of the splitting is electro-optic birefringence.
© 2004 Optical Society of America
(160.2100) Materials : Electro-optical materials
(190.1450) Nonlinear optics : Bistability
(190.2640) Nonlinear optics : Stimulated scattering, modulation, etc.
(230.5440) Optical devices : Polarization-selective devices
(260.1440) Physical optics : Birefringence
Michael Sánchez, Pengyue Wen, Matthias Gross, and Sadik Esener, "Polarization anisotropy in vertical-cavity semiconductor optical amplifiers," Opt. Lett. 29, 1888-1890 (2004)