Data and Time November 14, 2008, 3:15-4:15 PM
Location Bahen Center for Information Technology (BA), Room 1190
Host Alex Wong

An optical micro cavity for sensing application

Alan Xu

The Edward S. Rogers Sr. Department of Electrical and Computer Engineering (Photonics)


Optical devices can be used in a biochemical and gas sensor to help diagnose disease and monitor environment. Conventional optical sensors are bulky and expensive or involve discrete components such a microscope or a spectrometer. All of the bulky medical instruments can be replaced by a microscopic entity, called an optical microcavity, which has small sensing area and only requires analyte as little as 1 femtolitre. Additionally, an integrated micocavity sensor is small enough to be contained in a capsule, which can be ingested by patients. A periodic arrangement of nanometer-sized dielectric pillars is a promising platform to make a microcavity for sensing: in addition to their small size, it also contains more than 80% of void space for materials to infiltrate. During my Ph.D. study, I designed and fabricated pillar-array-based microcavities on a silicon platform. I also experimentally demonstrated a 0.2 nm wide resonance peak at 1550 nm. Leveraging on my research experience in microcavity design and fabrication, I plan to make an integrated optical device for sensing biomolecules.


Alan Xu got the Bachelor of Engineering degree from Electronic Engineering Department, Tsinghua University, Beijing, China. After that,heI came to University of Toronto and studied for a master of applied science degree in Materials Science and Engineering department. During the study,he focused on the design and simulation of a nanowire array based photonic crystal cavity for lasering. In the Ph.D. study in ECE department of University of Toronto, he mainly did research to implement a pillar-array based photonic crystal cavity with conventional microelectronic fabrication techniques on a silicon platform. The cavity is designed for sensing application.