We have developed a technology to integrate a thin layer of liquid crystal (LC) on top of a Vertical-Cavity Surface- Emitting Laser (VCSEL). Based on this technology, we demonstrate VCSELs with a chiral liquid crystal (CLC) layer, which acts as a tuneable mirror. The reflection properties of the CLC layer are controlled by temperature. Next we demonstrate VCSEL devices with tuneable external cavity using a nematic LC layer incorporated with an additional dielectric mirror (SiO₂/Ta₂O₅). The VCSEL and the LC layer can be electrically driven independently and the optical length in the external cavity can be tuned by the applied voltage on the LC layer. In both configurations we show that the emission properties of the VCSEL can be changed, in terms of emission wavelength, polarization state and/or lasing threshold.

Date Published: 7 October 2014
PDF: 6 pages
Proc. SPIE 9182, Liquid Crystals XVIII, 918203 (7 October 2014); doi: 10.1117/12.2058863

Published in SPIE Proceedings Vol. 9182:
Liquid Crystals XVIII
Iam Choon Khoo, Editor(s)