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Updated: Jul 16, 2026
10:42
Infrared Degenerate Four-wave Mixing with Upconversion Detection for Quantitative Gas Sensing
Published on: March 22, 2019
Coupled-mode theory for infrared and submillimeter wave detectors
George Saklatvala1, Stafford Withington, Michael P Hobson
1Department of Physics, University of Cambridge, Cambridge, UK. g.saklatvala@mrao.cam.ac.uk
Summary
We developed a general theory for submillimeter-wave and far-infrared power detectors. This framework models detector behavior across various light conditions and enables experimental determination of detector properties.
Area of Science:
- Physics
- Optical Engineering
- Electromagnetics
Background:
- Submillimeter-wave and far-infrared detectors are crucial for various scientific applications.
- Existing theories often lack generality for diverse detector types and light conditions.
Purpose of the Study:
- To present a comprehensive, spatiotemporal, modal theory for submillimeter-wave and far-infrared power detectors.
- To provide a flexible framework for modeling detector behavior and instrument performance.
Main Methods:
- Developed a theory based on the contraction of coherence tensors.
- Incorporated detector physics into a generalized coherence tensor.
- Derived expressions for statistical output properties and inter-detector correlations.
Main Results:
- The theory is applicable to detectors of any bandwidth, polarization, and coherence.
- It accommodates both quasi-monochromatic and pulsed light systems.
- Demonstrated that the detector tensor is a measurable quantity and outlined its experimental determination.
Conclusions:
- The presented theory offers a unified and general approach to understanding detector-light interactions.
- It provides a powerful tool for modeling diverse detector systems and optical instruments.
- Facilitates experimental characterization and design of advanced detector arrays and interferometers.
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