Open Access. Powered by Scholars. Published by Universities.®

Electrical and Computer Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 3 of 3

Full-Text Articles in Electrical and Computer Engineering

Microfiber Coupler Based Label-Free Immunosensor, Lin Bo, Christy Charlton O'Mahony, Yuliya Semenova, Niamh Gilmartin, Pengfei Wang, Gerald Farrell Apr 2014

Microfiber Coupler Based Label-Free Immunosensor, Lin Bo, Christy Charlton O'Mahony, Yuliya Semenova, Niamh Gilmartin, Pengfei Wang, Gerald Farrell

Articles

Optical microfibers and related structures which incorporate large evanescent field and minimal size offer new opportunities for biosensing applications. In this paper we report the development of an immunosensor based on a tapered microfiber coupler embedded in a low refractive index polymer. Biomolecules adsorbed on the microfiber coupler surface modify the surrounding refractive index. By immobilizing antigens on the surface of the sensing area, the microfiber coupler was able to operate as a label-free immunosensor to detect specific antibodies. We experimentally demonstrated for the first time the sensing ability of this sensor using a fibrinogen antigen-antibody pair. By monitoring the …


Modeling A Sensor To Improve Its Efficacy, Nabin K. Malakar, Daniil Gladkov, Kevin H. Knuth May 2013

Modeling A Sensor To Improve Its Efficacy, Nabin K. Malakar, Daniil Gladkov, Kevin H. Knuth

Physics Faculty Scholarship

Robots rely on sensors to provide them with information about their surroundings. However, high-quality sensors can be extremely expensive and cost-prohibitive. Thus many robotic systems must make due with lower-quality sensors. Here we demonstrate via a case study how modeling a sensor can improve its efficacy when employed within a Bayesian inferential framework. As a test bed we employ a robotic arm that is designed to autonomously take its own measurements using an inexpensive LEGO light sensor to estimate the position and radius of a white circle on a black field. The light sensor integrates the light arriving from a …


Coupled Photonic Crystal Micro-Cavities With Ultra-Low Threshold Power For Stiumulated Raman Scattering, Qiang Liu, Zhengbiao Ouyang, Sacharia Albin Jan 2011

Coupled Photonic Crystal Micro-Cavities With Ultra-Low Threshold Power For Stiumulated Raman Scattering, Qiang Liu, Zhengbiao Ouyang, Sacharia Albin

Electrical & Computer Engineering Faculty Publications

We propose coupled cavities to realize a strong enhancement of the Raman scattering. Five sub cavities are embedded in the photonic crystals. Simulations through finite-difference time-domain (FDTD) method demonstrate that one cavity, which is used to propagate the pump beam at the optical-communication wavelength, has a Q factor as high as 1.254 × 108 and modal volume as small as 0.03μm3 (0.3192(λ/n)3). These parameters result in ultra-small threshold lasing power ~17.7nW and 2.58nW for Stokes and anti-Stokes respectively. The cavities are designed to support the required Stokes and anti-Stokes modal spacing in silicon. The proposed structure …