Sensors: Synthesis of Active Quantum Dot Infra-Red (IR) Sensors

Oklahoma State University, Stillwater OK

Investigators

Abstract

The objective of this Sensors and Sensor Networks (NSF 05-526) research is to acquire an understanding of the effects of mechanical strain on the infrared absorption of semiconductor nanocrystals which exhibit quantum confinement, referred to as quantum dots, thereby enabling their potential use as active infrared sensors. The approach will be to synthesize by ion implantation a range of semiconductor quantum dots implanted into infrared transparent substrates. Spectral response will be tailored by varying the quantum dot size. Resulting size, structure, distribution and chemistry will be quantified by Rutherford backscattering spectrometry, high resolution transmission electron microscopy and photoluminescence spectroscopy. Fine-tuning about a particular spectral peak will then be performed by the application of strain accomplished by piezoactuator loading. If successful the benefits of this research will be a new class of advanced infrared sensors with dramatically improved performance in multispectral and high sensitivity applications, including remote temperature sensing, trace gas sensing of chemical and biological species, military target discrimination and identification, and ground-based astronomy. The ability to actively tune the absorption spectra of quantum dots could lead to compact infrared sensors with lower cost, higher sensitivity and the ability to operate at room temperature. Additionally this work will contribute to an enhancement of infrastructure for research and education by the strong collaboration which reaches across both institutional and interdisciplinary bounds. Interaction with the scientists and engineers from the participating government laboratory will broaden the scientific experience of our graduate and undergraduate students involved with the project, and will promote understanding and awareness of interdisciplinary scientific collaboration.