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Long, Christopher Michael

Publications and source records attributed to Long, Christopher Michael.

Zero-Power Analog Optical Processing

The motivation behind this research is the growing challenge of handling the massive amounts of data generated by modern imaging systems. Conventional digital image processing techniques are struggling to keep pace with the demands of high-resolution and high-speed imaging systems for remote sensing due to their high-power consumption and data storage requirements. We present a novel approach based on analog photonics to address this challenge. The proposed system utilizes a silicon-photonics-based image encoder positioned after image formation and initial optical-to-electrical conversion. The photonic encoder compresses image data using a passive disordered photonic structure to perform kernel-type random projections of the raw data. The compressed data is then processed by a back-end neural network, which reconstructs the original image with high fidelity (structural similarity exceeding 90%). Our proposed approach has the potential to compress images with ~ 1000X lower power consumption compared to digital approaches with data rates exceeding 1 terapixel/second.

97 MATHEMATICS AND COMPUTING↗

Phase-wrapping method for beam steering in optical phased arrays

A method and apparatus are provided for controlling the phase shifts produced in a binary corporate tree network of the kind, e.g., that can drive a phased array for steering an optical beam. The method employs a novel phase-wrapping technique in which an entire layer of the binary tree is disabled when the phase added in that layer reaches 2π. With that technique, it is possible to economize on electrical control lines and on the use of electric power, while still maintaining the ability to produce arbitrary phases at the output of the tree network.

Gehl, Michael↗

Photonic integrated circuits for generating high-brightness squeezed light

A high-brightness squeezed light source includes a plurality of light squeezing elements and a photonic summing device. The light squeezing elements each output respective squeezed light responsive to receipt of unsqueezed light. The photonic summing device receives the squeezed light output by each of the light squeezing elements and coherently adds the squeezed light to generate a high-brightness squeezed light output. The high-brightness squeezed light output has a greater brightness than the outputs of the light squeezing elements, and a same degree of squeezing as one or more of the outputs of the light squeezing elements.

Soh, Daniel Beom Soo↗

Cryogenic C-band wavelength division multiplexing system using an AIM Photonics Foundry process design kit

Cryogenic environments make superconducting computing possible by reducing thermal noise, electrical resistance and heat dissipation. Heat generated by the electronics and thermal conductivity of electrical transmission lines to the outside world constitute two main sources of thermal load in such systems. As a result, higher data rates require additional transmission lines which come at an increasingly higher cooling power cost. Hybrid or monolithic integration of silicon photonics with the electronics can be the key to higher data rates and lower power costs in these systems. We present a 4-channel wavelength division multiplexing photonic integrated circuit (PIC) built from modulators in the AIM Photonics process development kit (PDK) that operate at 25 Gbps at room temperature and 10 Gbps at 40 K. We further demonstrate 2-channel operation for 20 Gbps aggregate data rate at 40 K using two different modulators/wavelengths, with the potential for higher aggregate bit rates by utilizing additional channels.

42 ENGINEERING↗