Length scales and polarization properties of transverse patterns in broad-area vertical-cavity surface-emitting lasers

Abstract

This work studies the patterns emitted by broad-area VCSELs with a square aperture of 40 /spl mu/ by 40 /spl mu/. The devices are oxide-confined top-emitters lasing at around 780 nm. By controlling the device temperature the above mentioned detuning can be changed and thus the length scales of the patterns. For decreasing temperatures the divergence angle of the emission (the transverse wave number) increases and fewer modes are selected resulting in a less complex pattern. This paper studies these relationships quantitatively and considers how to extract the value of the detuning experimentally. In the theory, phase lag in the spacer layer as well as the one in the Bragg reflector is taken into account. Additionally, this study looks into the polarization properties of the emission.