Photonic crystal (PhC) cavities made in broadband luminescent material offer attractive possibilities for flexible active
devices. The luminescence enables the cavity to operate as an autonomous entity. New applications of this property are
demonstrated for cavities made in the InGaAsP underetched semiconductor membrane with embedded InAs Quantum
Dots that emit in the range of 1400-1600 nm.
Planar photonic crystal membrane nanocavities were released from the parent chip by mechanical nanomanipulation.
The released cavity particle could be bonded on an arbitrary surface, which was exploited to make a novel fiber-optic tip
sensor with a PhC cavity attached to the tip.
A single mode from a short cavity is shown to couple simultaneously to at least three cavity modes of a long cavity, as
concluded from level anticrossing data when the small cavity was photothermally tuned.
Reconfigurable and movable cavities were created by locally varying the infiltration status by liquid oil near a PhC
waveguide or defect cavity. Liquid was displaced locally on a micron scale using capillary force effects or laser-induced
evaporation and condensation phenomena.
Results are presented on the use of InGaAsP photonic crystal nanobeam slot waveguides for refractive index
sensing. These sensors are read remote-optically through photoluminescence, which is generated by built-in InGaAs
quantum dots. The nanobeams are designed to maximize the electromagnetic field intensity in the slot region, which
resulted in record-high sensitivities in the order of 700 nm/RIU (refractive index unit). A cavity, created by locally
deflecting the two beams towards each other through overetching, is shown to improve the sensitivity by about 20%.
We study the electrical and optical characteristic of the width-reduced line-defect photonic crystal waveguides with lateral p-i-n structures on Silicon-on-Insulator substrates. A longitudinal-section-based electrical model is built to take the holes into consideration. Compared with the classical line-defect photonic crystal waveguides, the width reduced photonic crystal waveguide has much stronger capacity in optical confinement in plane, which can allow a narrower intrinsic layer that leads to a fast electric response.