Michael Shearn

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Although gigahertz-scale free-carrier modulators have been demonstrated in silicon, intensity modulators operating at terahertz speeds have not been reported because of silicon's weak ultrafast nonlinearity. We have demonstrated intensity modulation of light with light in a silicon-polymer waveguide device, based on the all-optical Kerr effect-the ultrafast(More)
We fabricated horizontal Si slot waveguides with a 25 nm SiO2 slot layer by bonding thin Si-on-insulator wafers. After removing the Si substrate and buried oxide from one side of the bonded structure, grating-coupled waveguides and ring resonators were partially etched into the Si /SiO2 /Si device layers. The gratings exhibit efficiencies of up to 23% at(More)
Hybrid Si/III-V, Fabry-Perot evanescent lasers are demonstrated, utilizing InGaAsP as the III-V gain material for the first time to our knowledge. The lasing threshold current of 300-mum-long devices was as low as 24 mA, with a maximal single facet output power of 4.2 mW at 15 degrees C. Longer devices achieved a maximal single facet output power as high as(More)
Plasma processing techniques are one of the cornerstones of modern semiconductor fabrication. Low pressure plasmas in particular can achieve high radical density, high selectivity, and anisotropic etch profiles at low temperatures and mild voltages. This gentle processing environment prevents unwanted diffusion and degradation of materials due to heat and(More)
S. J. B. Yoo,* J. P. Heritage, V. J. Hernandez, R. P. Scott, W. Cong, N. K. Fontaine, R. G. Broeke, J. Cao, S.-W. Seo, J.-H. Baek, F. M. Soares, Y. Du, C. Yang, W. Jiang, K. Aihara, Z. Ding, B. H. Kolner, Anh-Vu Pham, Shu Lin, F. Olsson, S. Lourdudoss, K. Y. Liou, S. N. G. Chu, R. A. Hamm, B. Patel, W. S. Hobson, J. R. Lothian, S. Vatanapradit, L. A.(More)
This paper describes the InP platforms for photonic integration and the development on these platforms of an optical code division multiple access (O-CDMA) system for local area networks. We demonstrate three building blocks of this system: an optical pulse source, an encoder/decoder pair, and a threshold detector. The optical pulse source consists of an(More)
By using a dry etch chemistry which relies on the highly preferential etching of silicon, over that of gallium (Ga), we show resist-free fabrication of precision, high aspect ratio nanostructures and microstructures in silicon using a focused ion beam (FIB) and an inductively coupled plasma reactive ion etcher (ICP-RIE). Silicon etch masks are patterned via(More)
We demonstrate modelocking of a colliding-pulse mode-locked laser formed by 3-μm-deep etched-mirrors on an InP platform for integration with passive waveguide components. Timing jitter of 243 fs and pulse width of 10 ps were measured. 1. Introduction Optical code division multiple access (O-CDMA) technology is a promising candidate for the next generation(More)
We describe a sample-processing micro-reactor that utilizes 60 GHz RF radiation with approximately 730 mW of output power. The instrument design and performance characterization are described and then illustrated with modeling and experimental studies. The micro-reactor's efficiency on affecting hydrolysis of chemical bonds similar to those within large(More)