Background
Mid to long-wave infrared detectors capture and interpret infrared radiation emitted by objects, and convert it into additional data. These detectors have wide ranging applications including gas sensing, thermal imaging, environmental monitoring, and defense applications. Typically, these detectors use micro- or nano-scale microwave-frequency acoustic wave resonators to detect weak and fast mid to long-wave infrared light. These resonators have small mode volumes and high quality factors, but they can have limitations in their sensitivity and selectivity, as well as complex fabrication processes.
Invention Description
Researchers at Arizona State University and Virginia Tech have developed a novel mid to long-wave infrared detector that uses a photonic crystal-defined acoustic wave resonator and metamaterial absorbers. The resonator has a designed resonant frequency, and can act as an oscillator when part of a signal loop with sufficient gain. When the frequency of the oscillator output is monitored, the intensity changes of the incoming infrared light can be observed and measured, providing unprecedented levels of infrared detection sensitivity and selectivity.
Potential Applications:
- Thermal imaging
- Gas leak detection & sensing
- Surveillance & security
- Environmental monitoring
- Industrial inspection
Benefits and Advantages:
- Minimizes environmental noise – rejects common-mode input
- Enhances infrared-induced frequency changes – two coupled mechanical resonators enhance frequency changes
- Extended bandwidth – senses differential temperature between two resonators
- High absorption – near 100% narrowband or multi-spectral broadband infrared absorption
- Improves selectivity & sensitivity – uses efficient methods to focus infrared input to active regions
