Electrically wavelength tunable laser based on one‐dimensional structure with liquid crystal defect layer

Abstract

AbstractThe localized state in a one‐dimensional photonic crystal having a liquid crystal defect layer can be controlled by applying a voltage. We used the light confinement effect of the photonic crystal and the shift in the localized state wavelength due to the introduction of a liquid crystal defect layer and tried to control the laser emission by optical pumping of the one‐dimensional photonic crystal having a liquid crystal defect layer and control the lasing wavelength upon applying an electric field. First, we used a dielectric multilayer of periodically stacked TiO2 and SiO2 layers as the one‐dimensional photonic crystal, introduced a nematic liquid crystal having excellent responsiveness to an external electric field as the defect layer that disrupts the periodicity, and verified that the peak wavelength can be controlled by applying a voltage based on the localized state in the one‐dimensional photonic band. These results agreed well with the numerical analysis results. Furthermore, we excited the dye‐doped liquid crystal by a pulse laser and measured the laser emission from the localized state wavelength. In addition, the emission wavelength was successfully modulated upon applying electric field. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 87(2): 1–8, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10173