Robert R. Krchnavek

Learn More
Hydroquinone (HQ) was used as the principal chemical reducing agent to prepare aqueous silver nanocolloids from silver nitrate. The data demonstrate that HQ is unable to initiate the particle growth process on its own, but is able to sustain particle growth in the presence of pre-existing metallic clusters. This unique selectivity is similar to that seen in(More)
To successfully exploit the benefits of optical technology in a tightly coupled multicomputer, the architectural design must reflect both the advantages and limitations of optics. This article describes a class of such architectures, based upon inverted-graph topologies. We consider the physical construction of these systems, demonstrating the relevant(More)
We report a simple technique for patterning channelized optical waveguides on standard electronic printed circuit card material. The technique exploits the abundance of transparent, radiant-curing polymer adhesives in the fiber optics and the dental industries. The process is compatible with standard printed circuit card fabrication processes; hence its(More)
To successfully exploit the benefits of optical technology in a tightly-coupled multicomputer, the architectural design must reflect both the advantages of optics and the limitations of optics. This paper describes a class of such architectures, based upon inverted graph topologies. Two instances of this class (an inverted hy-percube and an inverted mesh)(More)
— Single-mode optical D-fiber is fabricated and coupled to single-mode acrylic waveguides by use of a novel technique utilizing alignment ways and a transcision. The D-fiber is fabricated by lapping the cladding layer of a single-mode fiber to the core. Optical waveguides and alignment ways are made with polymers by photolithography. This technique allows(More)
Nanoimprint lithography has been shown to be a viable means of patterning polymer films in the sub-100 nm range. In this work, we demonstrate the use of a bilayer resist to facilitate the metal liftoff step in imprinter fabrication. The bilayer resist technology exhibits more uniform patterns and fewer missing features than similar metal nanoparticle arrays(More)
Highly efficient, reliable packaging of semiconductor optical devices such as lasers and optical amplifiers remains an expensive and challenging task. In this paper, we present an approach to single-mode fiber coupling which results in relaxed alignment tolerances during the package assembly process, while maintaining coupling efficien-cies as high as(More)
iOS is Apple's mobile operating system and is presently used on the iPhone, iPad, and iPod Touch. The hardware platforms associated with the iOS operating system provide a powerful platform for sensor applications. In this paper, we provide a case study on the development of a digital multimeter (DMM) using an iPod Touch. The DMM case study addresses the(More)
In spite of the clear bandwidth advantages of optical technologies, current comme rcial multicomputers are still designed exclusively using electronic interconnects. This is due, in part, to the manufacturing complexity of existing optical interconnects, as well as architectural designs that are optimized for electrical rather than optical technology. We(More)