Photonics & Microsystems
VCSEL laser technology is a new laser advance for Solid State Lighting suitable for LED manufacturers, applications include automobile headlighting.
Coherent Perfect Absorber that completely absorbs incoming radiation with zero reflection, applications in free-space and on-chip optical communications.
High power mid-IR laser >1W with high directionality, co-developed with Princeton University.
Imprint lithography, based on the mechanical embossing of a polymer, can achieve pattern resolutions beyond the limitations set by the light diffractions or beam scattering in other techniques.
Light can exert a force through two separate mechanisms: radiation pressure, which exerts a force in the direction of the light, and a gradient force, which acts in a transverse direction. Yale researchers have demonstrated for the first time that the transverse gradient force can be harnessed in integrated silicon photonic circuits. A free standing optical waveguide is driven by the gradient optical force generated by asymmetrically engineering the lightwave mode in the waveguide. Due to the strong confinement of light in the submicron waveguide, the optical force is significantly enhanced at small dimensions, with the level of actuation comparable to electrostatic and piezoelectric methods. This device paves the way for optically-actuated nanomechanical devices operating under a new physical principal - waveguide light force - that is fundamentally different from conventional appoaches.
Yale researchers have developed an all N-channel CMOS (Complementary Metal-Oxide-Semiconductor) technology that overcomes the problem of low hole mobility. Yale’s novel technology utilizes the double channel capability of a MOSFET built with a SOI (semiconductor on insulator) structure to eliminate P-channels and replace them with N-channels, resulting in increased switching speed. This technology can be implemented with both silicon and III-V semiconductors.
Yale researchers have successfully designed a laser source with the parameters to realize spatially incoherent laser emission. The spatial incoherence of the light eliminates speckle and coherent crosstalk without sacrificing laser-like intensities. Random lasers have the potential to replace LEDs in imaging applications.
A 1-step electrochemical etch (EC) process for gallium nitride (GaN) epi-wafers post mesa- etch which creates Distributed Bragg Reflector (DBR) mirrors. The result is significantly increased LED light efficiency; photoluminescence testing shows a 5x increase in light intensity. This is a dramatic improvement over the current state of the art, e.g. backscattering by substrate patterning. Etch rate is typically 5 microns/minute.
Imperfect modal matching and finite photon absorption rates have usually limited the maximum attainable detection efficiency of single photon detectors. Yale University researchers have demonstrated a high quantum efficiency single photon detector (>90%), fully embedded in a scalable, low loss silicon photonic circuit at 4 Kelvin that provides ultrashort timing jitter of 18ps at multi-GHz detection rates. The dark count rate also drops to below 0.1Hz at optimal biasing. The detector's novel evanescent waveguide drastically increases the absorption length for incoming photons. The fibre based detector couples in light with low insertion loss. The energy resolution is as low as 1x10-19W/Hz1/2.