Nanoantennas on Nanowire-Based Optical Sensors

Abstract

This chapter presents a theoretical analysis and experimental study with regard to nanoantennas for use with carbon nanotubes (CNT) -based IR sensors. It presents a comprehensive mathematical model that accounts for the quantum-confinement effects on the conductivity and dielectric function of the nanoscale antenna-to theoretically predict the electric field-enhancement effect for different configurations of the antenna structure and the CNT sensor. In addition, it describes the design and fabrication process for nanoantennas for quantum IR detectors. By integrating the nanoantenna, the incident electric field at the sensor was enhanced such that the photocurrent of the sensor was greatly increased. Several factors for affecting the gain of the antenna are discussed and their effects are demonstrated and compared to the response of the detector with antennas of different geometries. Based on this understanding, the developed enhancement technology provides a dramatic improvement in the performance of infrared sensors. In the future, it is anticipated gaining greater insight into the localization of light and its control relating to semiconductor nanostructures. To date, localization of light has only been achieved using metallic nanostructures. © 2012 Elsevier Inc. All rights reserved.