- 4:00 pm on Wednesday, April 9, 2014
- Photonics Center, 8 Saint Mary’s St., Room 211
Interferometric Plasmonic Biosensor Arrays for High-Performance Label-Free Biomolecular Detection
With Dr. Filbert Bartoli
Chandler Weaver Chair
Department of Electrical & Computer Engineering
Refreshments will be served outside Room 339 at 3:45 p.m.
Faculty Host: Enrico Bellotti
Abstract: We investigate a class of plasmonic interferometric biosensors that consist of arrays of circular aperture-groove nanostructures patterned on a gold film for phase-sensitive biomolecular detection. These biosensors achieve superior performance within a microscale footprint by combining SPR interactions with sensitive interferometric techniques. The phase and amplitude of interfering surface plasmon polaritons (SPPs) in the proposed device can be effectively engineered by structural tuning, providing a flexible and efficient control over the plasmon line shape observed through SPP interference. Spectral fringes with high contrast, narrow linewidth, and large amplitude have been experimentally measured and permit sensitive detection of protein surface coverage as low as 0.4 pg/mm2. This sensor resolution compares favorably with commercial prism-based surface plasmon resonance systems (0.1 pg/mm2), but is achieved here using a significantly simpler collinear transmission geometry, a miniaturized sensor footprint, and a low-cost compact spectrometer, showing great promise to develop fast, inexpensive, compact biomedical devices. Furthermore, we also demonstrate superior sensor performance using intensity interrogation method, which incorporates CCD imaging to upgrade our platform for high-throughput array sensing. A novel low-background interferometric sensing scheme yields a record high sensing figure of merit (FOM*) of 146 in the visible region, surpassing previous plasmonic biosensors and facilitating ultrasensitive high-throughput detection.
(Based off of work by Yongkang Gao, Beibei Zeng, Qiaoqiang Gan, Xuanhong Cheng, and Filbert J. Bartoli)
About to Speaker: Dr. Filbert Bartoli is currently the Chandler Weaver Chair and Professor of Electrical & Computer Engineering (ECE) at Lehigh University and Chair of the Electrical and Computer Engineering Department. From 2000 to 2005, he served as a Program Director in the Division of Electrical and Communications Systems at the National Science Foundation. Prior to that he was at the Naval Research Laboratory, where he was the Head of the Advanced Materials Section in the Optical Sciences Division. He is a Fellow of OSA and IEEE, and recently served as IEEE Photonics Society Vice President for Finance and Administation and Editor-in-Chief for the IEEE Journal of Selected Topics in Quantum Electronics. His research activities have included a broad range of topics, such as infrared detection, inorganic and organic optoelectronics, semiconductor physics, quantum well devices physics, and nonlinear optics. His current research interests include nanophotonics and plasmonics for biosensors, solar cells, and slow light applications. His research publications include over 320 technical papers and 19 patents.