Photonic integrated circuit technology (silicon photonics) is used for many applications including optical data communications, optical and quantum computing, and sensing including LiDAR, biomedical and environmental. A major packaging challenge facing the industry is optical coupling between multiple integrated photonic components together with low insertion loss, in a cost effective manner, into a package suitable for commercialization. A promising approach is to create “photonic wire bonds” (PWBs), namely optical waveguides that look similar to conventional electrical wire bonds. PWBs are a high-yield, low-insertion-loss, and high-throughput versatile method of packaging photonic components such as chip-to-fiber and laser-to-chip interconnects. Utilizing two-photon polymerization to fabricate freeform 3D polymer structures, PWBs can connect components with arbitrarily disparate mode field shapes and sizes. Capabilities and advantages of the PWB technique include: gain chip integration with existing ’known good die’, dense optical I/O connections to the chip, scalability from prototyping to high-volume, and interconnects that are not possible with other standard photonic packaging techniques. Speaker(s): Lukas Chrostowski, Virtual: https://events.vtools.ieee.org/m/372682

Title: Millimeter-wave Reconfigurable Intelligent Surfaces for 5G and Future Wireless Communications Abstract: Millimeter-waves (mmWaves, 30-300 GHz) cover much shorter distances than the sub-6GHz signals due to absorption and/or strong scattering from most materials in a typical communication channel. As such, it is very common for the user equipment (UE) to receive unacceptably low signal-to-noise (SNR) signals or experiencing no coverage at all. Densifying the base station (BS) network is an approach that will improve signal coverage, this comes at a substantial capital expenditure due to the costs associated with the hardware, installation, and maintenance of such complicated systems. Alternatively, passive reconfigurable intelligent surfaces (RISs) are potential solutions to the mmWave coverage challenges and have attracted great interest in the recent years from both academia and industry. RISs are low cost, low profile planar devices capable of redirecting incident mmWaves to a desirable direction(s) without generating an RF power (passive) thus being potentially ultra-low power systems. In this presentation, I will provide a brief background for the RIS circuits and systems, review relevant prior work, and present our proposed and fabricated RIS designs. I will also discuss the deployment of RISs in real-world wireless communication scenarios. The talk will end with potential future RIS architectures and new sensing and imaging applications. Biography: Georgios Trichopoulos received the Diploma degree in electrical and computer engineering from the Democritus University of Thrace, Xanthi, Greece, in 2004, the M.S. degree in biomedical engineering from the National Technical University of Athens and University of Patras, Greece (under a joint program), in 2006, and the Ph.D. degree in electrical and computer engineering from The Ohio State University, Columbus, OH, USA, in 2013. From 2013 to 2015, he was a Postdoctoral Researcher with the ElectroScience Laboratory, The Ohio State University. His research areas include electromagnetic theory, terahertz imaging, antenna design for millimeter-wave and terahertz sensors, and high-frequency reconfigurable metasurfaces. He is currently an Associate Professor with the School of Electrical, Computer, and Energy Engineering, Arizona State University, Tempe, AZ, USA. Dr. Trichopoulos has been the recipient of several awards, including the Best Student Paper Award of the 2013 IEEE Antennas and Propagation Symposium and 2019 NSF CAREER Award. Virtual: https://events.vtools.ieee.org/m/377668