Quantum results could facilitate the detection of mid-infrared light at room temperature. Researchers from the Universities of Birmingham and Cambridge have presented a groundbreaking technique for detecting mid-infrared (MIR) light at room temperature using quantum systems.
The research, published in the journal Nature Photonics, was carried out at Cambridge’s Cavendish Laboratory and is a major step forward in scientists’ ability to gain insight into the workings of chemical and biological molecules.
In a new method using quantum systems, the team converted low-energy MIR photons into high-energy visible photons using molecular emitters. The new innovation could help scientists detect MIR and perform single-molecule-level spectroscopy at room temperature.
D., an associate professor at the University of Birmingham and lead author of the study. Rohit Chikkaraddy explained, “The bonds that keep atoms in molecules apart can vibrate like springs, and these vibrations resonate at very high frequencies. These arcs can be disturbed by light in the mid-infrared region, which the human eye can’t see. At room temperature, these springs perform chaotic movements, which is the reason for detecting mid-infrared light. “This means that the main problem is to avoid thermal noise. Current detectors rely on bulky, refrigerated semiconductor devices that need a lot of power, but our research offers an exciting new way to detect this light at room temperature.”
The new approach is called MIR pulsating luminescence (MIRVAL) and uses molecules capable of being both MIR and visible light. The team was able to combine molecular emitters in a very small plasma cavity that resonates in both the IR and visible ranges. They then designed it in such a way that the vibrational states of the molecules and the electronic states could interact, effectively converting the MIR light into enhanced visible brightness.
Dr. “The most challenging part was combining three completely different length scales—visible wavelengths of hundreds of nanometers, molecular vibrations of less than one nanometer, and mid-infrared wavelengths of tens of thousands of nanometers—into one platform,” Ciccaraddy continued.
By creating picocasons, which are incredibly tiny light-catching voids created by single-atom defects on metal surfaces, the researchers were able to achieve an extraordinary light-catching volume of less than a cubic nanometer. This meant that the team could limit MIR light to a single molecule scale.
This breakthrough has the capacity to deepen the understanding of complex systems and pave the way for infrared active molecular vibrations that are often inaccessible at the single molecule level. However, MIRVAL can be useful in many fields beyond purely scientific research.
Dr Ciccaraddy concluded: “MIRVAL could have many applications, such as real-time gas sensing, medical diagnostics, astronomical research, and quantum communications, as we can now see the vibrational signatures of individual molecules at MIR frequencies. The ability to detect MIR at room temperature is a key part of research in this area. Thanks to further development, this new method not only finds application in practical devices that will determine the future of WORLD technologies, but also opens the possibility of sequentially manipulating the complex interaction of “spring balls” atoms in molecular quantum systems.
Source: Port Altele
