Related Experiment Video
Updated: May 5, 2026
10:42
Infrared Degenerate Four-wave Mixing with Upconversion Detection for Quantitative Gas Sensing
Published on: March 22, 2019
8.0K
Long-wave infrared detection based on difference-frequency generation up-conversion
Optics Express
|May 4, 2026
Summary
This study introduces a novel room-temperature device for detecting long-wave infrared (LWIR) light using frequency upconversion. It offers high sensitivity and performance without cryogenic cooling, overcoming limitations of current LWIR detectors.
Area of Science:
- Optics and Photonics
- Infrared Spectroscopy
- Materials Science
Background:
- The long-wave infrared (LWIR) band is crucial for industrial, biomedical, and spectral analysis applications.
- Current frequency conversion methods for LWIR light (above 5 μm) are inefficient due to crystal limitations and absorption losses.
- Standard mercury cadmium telluride (HgCdTe) detectors require costly cryogenic cooling for high signal-to-noise ratios (SNRs).
Purpose of the Study:
- To develop a room-temperature LWIR detection device using frequency upconversion technology.
- To enable high-sensitivity LWIR detection without the need for cryogenic cooling.
- To address the limitations of existing LWIR detection technologies.
Main Methods:
- Utilized frequency upconversion technology for LWIR detection.
- Operated the device at room temperature across a broad spectral range (7.5–9 μm).
- Evaluated system performance including minimum detectable energy, wavelength stability, and responsivity.
Main Results:
- Achieved a minimum detectable energy at the femtojoule (fJ) level under nanosecond-pulse operation.
- Demonstrated high sensitivity and excellent wavelength stability for LWIR detection.
- Showcased a sensitivity improvement of up to 2.4 orders of magnitude compared to commercial HgCdTe detectors at room temperature.
Conclusions:
- The developed device offers a viable pathway for room-temperature, low-cost, high-performance LWIR detection.
- This technology significantly enhances detection accuracy and SNRs for LWIR signals under ambient conditions.
- Potential applications include real-time monitoring, portable sensing, and advanced spectroscopic analysis.
Related Concept Videos
01:09Infrared (IR) Spectroscopy: Overview
6.8K
When electromagnetic radiation passes through a material, atoms or molecules transition from a lower to a higher energy state by absorbing radiation corresponding to the energy difference between the two states. The absorption of infrared (IR) radiation causes transitions between vibrational energy levels in a molecule. Therefore, IR spectroscopy is a useful analytical tool for determining the molecular structure of molecules.
Different compounds display unique properties due to their...
Different compounds display unique properties due to their...
6.8K
01:25IR Spectrometers
3.1K
There are two main infrared (IR) spectrophotometers: dispersive IR spectrometers and Fourier transform infrared (FTIR) spectrometers. In a dispersive IR spectrometer, a beam of infrared radiation produced by a hot wire is divided into two parallel equal-intensity beams using mirrors. One beam passes through the sample, while another is a reference beam. The beams then move through the monochromator, which separates the radiations into a continuous spectrum of different frequencies. The...
3.1K
01:03IR Frequency Region: Fingerprint Region
2.1K
IR spectra are divided into two main regions: the diagnostic region and the fingerprint region. The diagnostic region of the spectrum lies above 1500 cm−1. The absorptions resulting from single-bond vibrations of the N–H, C–H, and O–H stretch at higher wavenumbers and appear on the left side of the spectrum. The stretching absorptions of the C≡C and C≡N occur between 2100–2300 cm−1. In contrast, those arising from stretching absorptions of the...
2.1K
01:24IR Frequency Region: X–H Stretching
1.5K
In IR spectroscopy, signals produced by the X−H bonds (such as C−H, O−H, or N−H) can be observed in the frequency range of 2700–4000 cm–1. The C−H stretching vibration forms sharp bands in the region 2850–3000 cm–1. The presence of the O−H stretching vibration leads to the forming of an absorption band in the frequency range 3650–3200 cm−1. At the same time, N−H stretching can be confirmed by absorption bands in...
1.5K
01:21IR Absorption Frequency: Hybridization
1.5K
Hydrocarbons such as alkanes, alkenes, and alkynes show characteristic C–H stretching absorption bands. These IR stretching frequencies depend on the hybridization of the involved carbon atom and can be explained in terms of the s character of each hybridized atomic orbital.
Among the sp, sp2, and sp3 hybridized orbitals, sp orbitals have the maximum s character (50%). Consequently, the electrons are held more closely to the nucleus, resulting in stronger and shorter C–H bonds that...
Among the sp, sp2, and sp3 hybridized orbitals, sp orbitals have the maximum s character (50%). Consequently, the electrons are held more closely to the nucleus, resulting in stronger and shorter C–H bonds that...
1.5K
01:24IR Spectroscopy: Molecular Vibration Overview
5.8K
When Infrared (IR) radiation passes through a covalently bonded molecule, the bonds transition from lower to higher vibrational levels. The fundamental vibrational motions that result in infrared absorption can be classified as stretching or bending vibrations.
Stretching vibrations are vibrational motions that occur along the bond line, changing the bond length or distance between two bonded atoms. They are further distinguished as symmetric or asymmetric. In symmetric stretching, the...
Stretching vibrations are vibrational motions that occur along the bond line, changing the bond length or distance between two bonded atoms. They are further distinguished as symmetric or asymmetric. In symmetric stretching, the...
5.8K