Infrared Photodetectors with Dirac Semimetals (ii(3): Electronic Sensing)
Abstract
Photodetectors that can operate at mid-to-long infrared (IR) wavelengths (2-16 µm) are of substantial interest to technologies ranging from satellite-to-earth communication, night vision, free space optical communication, molecular imaging, military tracking, remote sensing, and interconnects. Fast, broad-band, room-temperature photodetection in the mid-IR and terahertz spectral ranges still presents significant challenges. The main objective of the proposed project is develop photodetectors that are based on epitaxial thin films of recently discovered three-dimensional Dirac semimetals, such as cadmium arsenide. The unique electronic structure of three-dimensional Dirac semimetals promises broadband photoresponse into the long IR and even THz spectral range and extremely fast operation speed due to their very high Fermi velocity. Initial experiments will focus on the fabrication of basic photodetectors with cadmium arsenide films grown by molecular beam epitaxy. The responsivity, current-voltage characteristics and frequency response will be measured and compared to existing technologies. As a next step, back-gated structures will be developed as needed for wavelength tunable photodetectors. The project also seeks to explore and utilize the unique nonlinear optical properties of topological semimetals, such as shift currents, to optimize detector performance in unbiased operation. Ultimately, the proposed project seeks to demonstrate routes to broadband, tunable, ultrafast photodetectors that can operate at room temperature in the mid-to-long infrared IR spectral range.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 03, 2022
- Source ID
- W911NF2210016
Entities
People
- Susanne Stemmer
Organizations
- Army Contracting Command
- United States Army
- University of California, Santa Barbara