Publications

For adaptive optics systems, there is a growing demand for wavefront sensors that operate at higher frame rates and with more pixels while maintaining low readout noise. Lincoln Laboratory has been investigating Geiger·mode avalanche photodiode arrays integrated with CMOS readout circuits as a potential solution. This type of sensor counts...

The International Technology Roadmap for Semiconductors is the go-to standard for predicting future technology requirements and driving global research and development in the semiconductor industry. This article serves as your roadmap to what it all means for optical lithography over the next 10 to 15 years.

Optical limiting by suspensions of Au nanoparticles is enhanced by several orders of magnitude with the use of complex plasmonic shapes, such as spined "nanourchins," instead of nanospheres. Similar enhancements are observed by changing the material of nanospheres from Au to Ag. The experiments, measuring intensity-dependent transmission over a wavelength...

The optical switching time of twisted-nematic liquid-crystal cells using the liquid crystals, 5CB (C,H,,-Ph-Ph-CN), 50CB(C,Hw O-Ph-Ph-CN) and PCH5 (C,H,,-Cy-Ph-CN) have been characterized as a function of temperature, prebias voltage and switching voltage, V. The transition time from 90 % to 10 % transmission scales as V-1.9 and is limited to...

An optical modulator in silicon based on a diode structure has been operated in both forward and reverse bias. This modulator achieves near state-of-the-art performance in both modes, thereby making this device idea for comparing the two modes of operation. In reverse bias, the device has a V[pi]L of 4.9...

A broadband, Mach-Zehnder-interferometer based silicon optical modulator is demonstrated, with an electrical bandwidth of 26 GHz and V[pi]L of 4 V·cm. The design of this modulator does not require epitaxial overgrowth and is therefore simpler to fabricate than previous devices with similar performance.

The fabrication of reliable InP-based Geigermode avalanche photodiode arrays is described. Arrays of up to 256 x 64 elements have been produced and mated to silicon read-out circuits forming single-photon infrared focal plane imagers for 1.06 and 1.5 mum applications.

We report an array of Shack-Hartmann wavefront sensors using high-fill-factor Geiger-mode avalanche detector quad cells hybridized to all-digital CMOS counting circuits. The absence of readout noise facilitates fast wavefront sensing at low light levels.

We report the first high-current photodiode based on the slab-coupled optical waveguide concept. The device has a large mode (5.8 x 7.6 um) and ultra-low optical confinement ([] ~ 0.05%), allowing a 2-mm absorption length. The maximum photocurrent obtained was 250 mA (R = 0.8-A/W) at 1.55 um.

We present a systematic study of Mach-Zehnder silicon optical modulators based on carrier-injection. Detailed comparisons between modeling and measurement results are made with good agreement obtained for both DC and AC characteristics. A figure of merit, static VpiL, as low as 0.24Vmm is achieved. The effect of carrier lifetime variation...