Mid-infrared spectroscopy is essential for identifying molecules in the physical, chemical, and medical sciences. However, obstacles such as conventional infrared light sources, detectors, and blackbody radiation noise hinder the miniaturization and sensitivity of infrared spectrometers. Quantum infrared spectroscopy offers a promising solution. It utilizes entangled photon pairs in the visible and infrared ranges, providing a new sensing technology that allows infrared spectroscopy analysis using detectors in the visible range, overcoming previous limitations.
However, the bandwidth of traditional quantum-entangled light sources is at most 1 m or less, which hinders broadband measurements, which are critical in spectroscopic applications.
A research team led by Kyoto University has tackled the challenge of infrared spectroscopy by introducing quantum light sources. Their groundbreaking ultra-wideband quantum entanglement source produces a wider range of infrared photons (2 m to 5 m wavelengths).
Shigeru Takeuchi of the Department of Electronic Science and Engineering emphasized that this achievement opens the door to a significant reduction in the size of the system and an increase in the sensitivity of the infrared spectrometer.
The researchers envision a future where their compact, high-performance, battery-powered scanners will replace bulky and power-hungry equipment, facilitating field materials testing in various fields, including environmental monitoring, medicine, and safety.
"We can obtain spectra of a variety of target samples, including hard solids, plastics, and organic solutions," Takeuchi said. Shimadzu, our partner in the development of quantum optical devices, agrees that broadband measurement spectra are very convincing for distinguishing between substances in various samples. ”
Although quantum entangled light is not a new concept, its bandwidth in the infrared region is usually limited to a narrow range of 1 m or less. The innovation of this technology lies in taking advantage of the unique properties of quantum mechanics, such as superposition and entanglement, to overcome the limitations of traditional methods.
The research team has introduced a self-developed chirped quasi-phase matching device for the generation of quantum-entangled light. The device takes advantage of the chirp effect, which is a gradual change in the polarization reversal period of the component, to generate quantum photon pairs over a wide frequency band.
The goal is to improve the sensitivity of quantum infrared spectroscopy and advance quantum imaging in the infrared region as part of the team's broader efforts to develop practical quantum technologies.
Quantum entanglement source