Researchers from the University of Science and Technology of China have developed a new spectroscopic system that could significantly enhance molecular fingerprinting and atmospheric sensing capabilities, with potential applications in the energy industry.
The team, led by Professor Qiang Zhang, has resolved a long-standing trade-off in mid-infrared spectroscopy, where systems could not simultaneously achieve broad bandwidth, high photon flux, and high frequency accuracy. Their new system, based on difference frequency generation driven by widely tunable, near-infrared diode lasers traceable to atomic standards, achieves continuous tunability across the 3-3.7 μm atmospheric window, delivering output power exceeding 45 mW with an absolute frequency accuracy of 7.2 MHz.
In their research, published in the journal Nature Communications, the team demonstrated the system’s capabilities by overcoming a critical barrier in integrated photonics. They were able to unambiguously identify and eliminate hydrogen-induced absorption in silicon nitride microresonators, achieving an 88-fold reduction in optical loss. They also revealed multi-phonon absorption in the silica cladding as the fundamental limit to mid-infrared integrated photonics.
The system’s versatility was further showcased through scattering-resilient LiDAR capable of penetrating optically dense fog, and dual-modality sensing that simultaneously retrieves target distance and chemical composition. This new architecture unifies the rigor of frequency metrology with the versatility of broadband sensing, establishing a new paradigm for multi-dimensional perception in complex environments.
For the energy industry, this research could lead to improved atmospheric sensing capabilities, enabling more accurate monitoring of greenhouse gas emissions and air quality. The enhanced molecular fingerprinting capabilities could also facilitate better analysis of complex energy mixtures, such as biofuels and other alternative energy sources. Additionally, the scattering-resilient LiDAR technology could improve safety and efficiency in energy infrastructure monitoring, particularly in harsh or hazardous environments.
The researchers’ work represents a significant advancement in spectroscopic technology, with potential applications that could benefit the energy sector and beyond. As the technology is further developed and commercialized, it could play a crucial role in addressing some of the most pressing challenges in energy and environmental monitoring.
This article is based on research available at arXiv.