Lasing at bend, branch and intersection of photonic crystal waveguides

The authors report room temperature lasing by pulsed photopumping at line and point composite defects, i.e. a 60°-bend, a Y-branch and an intersection of single line defect waveguides, in a GaInAsP photonic crystal slab. The lasing wavelength was different from the simple line defect lasing mode. This indicates that such waveguide components act as microcavities with localised modes.