GOALI: Infrared Optical Microcavity Sensors for High-Sensitivity, High-Specificity Molecular Detection.

University Of Arizona, Tucson AZ

Investigators

Abstract

Infrared Optical Microcavity Sensors for High-Sensitivity, High-Specificity Molecular Detection. Intellectual merit: The goal of this proposal is to develop novel optical sensors that have enough sensitivity for single-molecule detection while also providing high selectivity without the need for surface functionalization or labeling. Our strategy will consist in developing optical microcavities operating in the infrared domain. Microcavities with high Q-factors permit to confine light for a long time and build up high intensity within the optical cavity. This allows the light signal to sample a target molecule many more times and increases the detection sensitivity by orders of magnitude down to the single molecule resolution. Current optical resonator technologies are based on oxide glass materials which have an optical transmission window limited to about 2 um. This preclude from accessing the infrared domain between 2-16 um. In this project we will build on our long experience with chalcogenide glasses to produce sensors based on fibers and resonant microspheres with high transparency over the entire mid-IR region. Here, we propose to build and test the first technique capable of achieving single-molecule detection while intrinsically providing high-selectivity for identification of target molecules. This research has the potential to induce a major leap forward in sensor technology. If successful, this project will provide a proof of concept for the first label-free, binding-agent-free optical sensor with single-molecule sensitivity and high molecular specificity. Broader Impact: The high sensitivity sensors developed in this project would have a direct societal impact. Detection of trace quantities of chemicals such as explosives or bio-hazardous substances has crucial implications for national security or bio-medical research. These fields require sensors that have high-sensitivity and are sufficiently versatile to identify a wide range of molecules. These sensors would also have many implications in the fundamental study of molecular processes for bio-technology and bio-medical research. Additionally, this research program will train students from underrepresented groups in the field of engineering and will directly involve undergraduate students in state-of-the-art research projects and aim at attracting promising students toward graduate studies in the Engineering Sciences. The proposed research will also be fully integrated into an international PhD program with our collaborators at the University of Rennes in France. Graduates students will perform course work and research activities alternately in both institutes and will gain a double PhD diploma. This will train our student to face the challenges of functioning in an international setting and will uniquely prepare them for future carrier in which they are increasingly likely to be exposed to international collaborations.