Amnon Yariv

Bio: Amnon Yariv is an academic researcher from California Institute of Technology. The author has contributed to research in topics: Laser & Semiconductor laser theory. The author has an hindex of 103, co-authored 1082 publications receiving 55256 citations. Previous affiliations of Amnon Yariv include University of California, Santa Barbara & Watkins-Johnson Company.

Charge domain bit serial vector-matrix multiplier and method thereof

Abstract: A charge domain bit serial vector matrix multiplier for real time signal processing of mixed digital/analog signals for implementing opto-electronic neural networks and other signal processing functions. A combination of CCD and DCSD arrays permits vector/matrix multiplication with better than 10 11 multiply accumulates per second on a one square centimeter chip. The CCD array portion of the invention is used to load and move charge packets into the DCSD array for processing therein. The CCD array is also used to empty the matrix of unwanted charge. The DCSD array is designed to store a plurality of charge packets representing the respective matrix values such as the synaptic interaction matrix of a neural network. The vector multiplicand may be applied in bit serial format. The row or sensor lines of the DCSD array are used to accumulate the results of the multiply operation. Each such row output line is provided with a divide-by-two/accumulate CCD circuit which automatically compensates for the increasing value of the input vector element's bits from least significant bit to most significant bit. In a similar fashion each row output line can be provided with a multiply-by-two/accumulate CCD circuit which automatically accounts for the decreasing value of the input vector element's bits from most significant bit to least significant bit. The accumulated charge packet output of the array may be preferably converted to a digital signal compatible with the input vector configuration by utilizing a plurality of analog-to-digital converters.

Holographic characterization of chain photopolymerization

Abstract: A holographic characterization technique is developed in accordance with a general photopolymerization model The technique allows detailed quantification of the chemical parameters, including their variation from the Trommsdorff effect The holographic procedure is especially suited for studying the diffusion of the chemical reactants

Single-electron analysis of the space-charge effect in free-electron lasers

Abstract: An exact treatment of the space-charge effect in the single-electron analysis of a free-electron laser is presented to calculate its small-signal gain. With the inclusion of the repulsive force between electrons, it is found that the trajectory of an electron can be solved from a generalized equation which includes a space-charge term. The results show the gain is saturated with decreasing growth rate due to high electron density. The radiation frequency is found to increase with the electron density and approach the value at plasma resonance. The condition ωpL/c = π clearly defines the boundary between the noninteracting and the collective regime of an electron beam, where ωp is the plasma frequency, L is the device length, and c is the light velocity in vacuum.

Phase-locked controlled filament laser

Abstract: A broad area semiconductor laser with induced self-focusing in the form of a phase-locked array of filaments is demonstrated. The multifilamentary laser has a single lobed and nearly diffraction limited far-field pattern, for injection currents up to I[approximately-equal-to]1.85Ith.

Optical annular resonators based on radial Bragg and photonic crystal reflectors

Abstract: A ring resonator based on Bragg reflection is studied in detail. Closed form expressions for the field and dispersion curves for radial Bragg gratings and photonic crystals based resonators are derived and compared to FDTD simulations. For strong confinement, the required gratings exhibit a chirped period and a varying index profile. Small bending radii and low radiation losses are shown to be possible due to the Bragg confinement. The sensitivity of the resonator characteristics to fabrication errors is analyzed quantitatively. A mixed confinement configuration utilizing both Bragg reflection and total internal reflection is also suggested and analyzed.

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

A comprehensive review of zno materials and devices

Abstract: The semiconductor ZnO has gained substantial interest in the research community in part because of its large exciton binding energy (60meV) which could lead to lasing action based on exciton recombination even above room temperature. Even though research focusing on ZnO goes back many decades, the renewed interest is fueled by availability of high-quality substrates and reports of p-type conduction and ferromagnetic behavior when doped with transitions metals, both of which remain controversial. It is this renewed interest in ZnO which forms the basis of this review. As mentioned already, ZnO is not new to the semiconductor field, with studies of its lattice parameter dating back to 1935 by Bunn [Proc. Phys. Soc. London 47, 836 (1935)], studies of its vibrational properties with Raman scattering in 1966 by Damen et al. [Phys. Rev. 142, 570 (1966)], detailed optical studies in 1954 by Mollwo [Z. Angew. Phys. 6, 257 (1954)], and its growth by chemical-vapor transport in 1970 by Galli and Coker [Appl. Phys. ...

Digital communications

Abstract: Spread Spectrum It’s not just for breakfast anymore! Don't blame me, the title is the work of this month's guest columnist, Steve Bible, N7HPR (n7hpr@tapr.org). While cruising the net recently, I noticed a sudden bump in the number of times Spread Spectrum (SS) techniques were mentioned in the amateur digital areas. While QEX has discussed SS in the past, we haven't touched on it in this forum. Steve was a frequent cogent contributor, so I asked him to give us some background. Steve enlisted in the Navy in 1977 and became a Data Systems Technician, a repairman of shipboard computer systems. In 1985 he was accepted into the Navy’s Enlisted Commissioning Program and attended the University of Utah where he studied computer science. Upon graduation in 1988 he was commissioned an Ensign and entered Nuclear Power School. His subsequent assignment was onboard the USS Georgia, a trident submarine stationed in Bangor, Washington. Today Steve is a Lieutenant and he is completing a master’s degree in computer science at the Naval Postgraduate School in Monterey, California. His areas of interest are digital communications, amateur satellites, VHF/UHF contesting, and QRP. His research area closely follows his interest in amateur radio. His thesis topic is Multihop Packet Radio Routing Protocol Using Dynamic Power Control. Steve is also the AMSAT Area Coordinator for the Monterey Bay area. Here's Steve, I'll have some additional comments at the end.

Plasmonics: Fundamentals and Applications

Abstract: Fundamentals of Plasmonics.- Electromagnetics of Metals.- Surface Plasmon Polaritons at Metal / Insulator Interfaces.- Excitation of Surface Plasmon Polaritons at Planar Interfaces.- Imaging Surface Plasmon Polariton Propagation.- Localized Surface Plasmons.- Electromagnetic Surface Modes at Low Frequencies.- Applications.- Plasmon Waveguides.- Transmission of Radiation Through Apertures and Films.- Enhancement of Emissive Processes and Nonlinearities.- Spectroscopy and Sensing.- Metamaterials and Imaging with Surface Plasmon Polaritons.- Concluding Remarks.