PhD Defense: "Terahertz Systems Engineering: Sources, Propagation, Phenomenology, Detectors, Design and Analysis"

Jon Suen

May 22nd (Thursday), 3:00pm
ITST, Bldg 937, Conference Room

The terahertz (THz) band, from 300 GHz to 20 THz, is the last remaining frontier of the electromagnetic spectrum. There is a rich set of phenomenology, science, and applications, which are only available with THz radiation. The THz engineer who is designing systems must be adept at integrating components with very limited performance into a system. This requires understanding and knowledge of a wide range of fields, including microwaves, infrared optics, material science, software development, atmospheric science, and the overall analysis and design of a system.

The design of such a system is fundamentally related to sensing science. Here, we have to consider detector and source technology, the propagation of radiation, target phenomenology, and the overall design and analysis of the system. I present research in all of these areas.

Specifically, in the field of THz phenomenology, I conducted a study to show the primary contrast mechanism in reflective biomedical imaging is water concentration. For source technology, I detail the development and characterization of photoconductive switches with record-breaking optical efficiency. In a separate study I developed a model which explains the complex photocarrier dynamics in fast-trapping THz photoconductive materials and show that high-frequency THz generation (>1 THz) is caused by beaching saturation.

My work in detectors shows the design of a quasi-optical radar that exploits low 1/f noise Schottky diodes for detection of slow moving objects, useful for biomedical sensing of respiration and heartbeat.

In the field of THz propagation, I have located low atmospheric water vapor sites and characterized THz attenuation on a global scale with satellite remote sensing data. Finally, I show the analysis of a full system by showing 300-gigabit level THz ground to geostationary satellite links to moderately dry global locations.

These projects inherently involved multidisciplinary research though they all were targeted towards the THz regime. This research exemplifies the broad knowledge and diverse fields that must be synergized to build effective THz systems and advance science in the THz domain.

About Jon Suen:

photo of jonathan suen Jonathan Y. Suen received an A.A. degree from Bard College at Simon’s Rock in 2002, the B.S. degree from the University of California, Santa Barbara in 2004, and the M.S. degree from the University of Michigan, Ann Arbor in 2005, all in Electrical Engineering. He is currently a doctoral candidate at the University of California, Santa Barbara in the Department of Electrical and Computer Engineering.

Since 2008 he has been a graduate student researcher at UCSB. His research centers on the development of terahertz systems and has published research on biomedical imaging, THz sources and components, as well as systems for communication and astrophysical observations.

Hosted by: Professor Philip Lubin and Chris Palmstrøm