Extended SWIR Single Photon Avalanche Photo Detector Technology For Bioimaging

The principal technical challenges associated with bioimaging include: 1) depth imaging - light scattering and diffraction in biological tissue; 2) photo-damage - classical high flux optical imaging causes photo-damage to cellular viability and perturbation to molecular biology for in situ imaging of biological processes rendering the sample unusable for repeat imaging and measurement of dynamic processes. Technologies utilizing single photon detectionshow promise of very low photon fluxes, single photon sensing, time gated photon sensing and ghost imaging using entangled photon pairs capabilities, to directly address the above challenges and limitations. While there is considerable activity towards the development of quantum photon sources (e.g., solid state lasers and systems for generation of entangled photons), there is significantly less R&D devoted to quantum photon detectors, i.e., single photon avalanche photodetectors (SPADs). Further, efforts on SPADs have been solely limited to those operating in the visible and telecommunications bands, and not in the biologically important 2080-2340 nm band which is a local minimum in the optical absorption of H2O. In this program Amethyst Research is developing a SPAD technology that will be able to deliver a new class of photodetectors directly addressing the current Ĺtechnology gapĺ of SPADs operating in the 2080-2340 nm window. These SPADs will be designed to be able to be integrated into avalanche photodiode arrays (for direct imaging), linear arrays for laser photon scanning imaging systems, or as single detectors for sensing. All Phase I Objectives Have All Been Successfully Met The overall Phase I Objective was to design and demonstrate the operation of a Single Photon Detector Technology operating in the 2080 ľ 2340 nm band for quantum biosensing and bioimaging community. All the following objectives/tasks where achieved. 1) Design and modeling of novel 2080-2340 nm GaSb-based SPAD device architectures, 2) Epitaxial growth of GaSb -based SPAD devices, 3) DC electro-optical characterization of GaSb -based SPAD devices, 4) Demonstration of superior performance of GaSb materials for SPAD devices, 5) System design and component and collaborator identification The Phase II Primary Objective is to fully develop and establish prototype manufacturing of a GaSb-based SPAD device operating in the 2080 -2340 band. Additional objectives are; Coordination and partnerships with research groups and laboratories engaged in development of bioimaging systems; Establish and Stress Test US based manufacturing supply chain to ensure manufacturing capability in the US. These detectors will provide a critically needed photodetector technology bioimaging, chemical sensing, quantum sensing and imaging.