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Chen, Ray T.

Publications and source records attributed to Chen, Ray T..

Neural network methods for radiation detectors and imaging

Recent advances in image data proccesing through deep learning allow for new optimization and performance-enhancement schemes for radiation detectors and imaging hardware. This enables radiation experiments, which includes photon sciences in synchrotron and X-ray free electron lasers as a subclass, through data-endowed artificial intelligence. We give an overview of data generation at photon sources, deep learning-based methods for image processing tasks, and hardware solutions for deep learning acceleration. Most existing deep learning approaches are trained offline, typically using large amounts of computational resources. However, once trained, DNNs can achieve fast inference speeds and can be deployed to edge devices. A new trend is edge computing with less energy consumption (hundreds of watts or less) and real-time analysis potential. While popularly used for edge computing, electronic-based hardware accelerators ranging from general purpose processors such as central processing units (CPUs) to application-specific integrated circuits (ASICs) are constantly reaching performance limits in latency, energy consumption, and other physical constraints. These limits give rise to next-generation analog neuromorhpic hardware platforms, such as optical neural networks (ONNs), for high parallel, low latency, and low energy computing to boost deep learning acceleration (LA-UR-23-32395).

edge computing↗

Slot waveguide with structural modulation

Apparatuses for communication or sensing are disclosed, the apparatuses comprising a substrate; a bottom cladding disposed on the substrate; a device layer disposed on the bottom cladding, wherein the device layer comprises: two substantially parallel rails extending from an input side to an output side of the device layer and configured to form a slot between the two substantially parallel rails, wherein each of the two substantially parallel rails comprises an inner edge adjacent to the slot and an outer edge opposite the slot; and one or more teeth coupled to each of the two substantially parallel rails; and a top cladding disposed onto the device layer and bottom cladding; wherein the bottom cladding, the device layer, and the top cladding are configured to support at least one optical guided mode. Other embodiments are described and claimed.

47 OTHER INSTRUMENTATION↗

Subwavelength photonic crystal waveguide in optical systems

An optical system is disclosed. The optical system comprising: a substrate; and a subwavelength photonic crystal waveguide atop the substrate, wherein the subwavelength photonic crystal waveguide comprises a periodic one or two-dimensional array of two or more interleaved dielectric pillars; wherein the periodicity of the one or two-dimensional array is constant, a combination of two or more periods, or random; wherein the one or two-dimensional array is substantially linear or curved; wherein each of the pillars of the one or two-dimensional array is at least one of a triangular prism, a trapezoidal prism, an elliptic cylinder, a cylinder, a tube, a frustum, a pyramid, a trapezoidal prism, and an asymmetric frustum; and wherein each of the pillars of the one or two-dimensional array comprises a solid, liquid, and/or gas. Other embodiments are described and claimed.

Xu, Xiaochuan↗

Method for Fabricating and Packaging an M.Times.N Phased-Array Antenna

A method for fabricating an M.times.N, P-bit phased-array antenna on a flexible substrate is disclosed. The method comprising ink jet printing and hardening alignment marks, antenna elements, transmission lines, switches, an RF coupler, and multilayer interconnections onto the flexible substrate. The substrate of the M.times.N, P-bit phased-array antenna may comprise an integrated control circuit of printed electronic components such as, photovoltaic cells, batteries, resistors, capacitors, etc. Other embodiments are described and claimed.

Subbaraman, Harish↗

Multiple-mode reconfigurable electro-optic switching network for optical fiber sensor array

This paper reports the first switching network compatible with multimode fibers. A one-to-many cascaded reconfigurable interconnection was built. A thin glass substrate was used as the guiding medium which provides not only higher coupling efficiency from multimode fiber to waveguide but also better tolerance of phase-matching conditions. Involvement of a total-internal-reflection hologram and multimode waveguide eliminates interface problems between fibers and waveguides. The DCG polymer graft has proven to be reliable from -180 C to +200 C. Survivability of such an electrooptic system in harsh environments is further ensured. LiNbO3 was chosen as the E-O material because of its stability at high temperatures (phase-transition temperature of more than 1000 C) and maturity of E-O device technology. Further theoretical calculation was conducted to provide the optimal interaction length and device capacitance.

Chen, Ray T.↗