Researchers from Scotland and Japan have developed the lightweight superconducting chip, which they say could unlock the full potential of terahertz imaging technologies and lead to the development of more poweful and portable devices.
Terahertz radiation lies between the microwave and infrared frequencies of the electromagnetic spectrum. It passes easily and harmlessly through a wide range of materials, and can be used to identify the characteristic ‘fingerprint’ of molecules and biological materials as it does so, allowing them to be detected and analysed.
Although terahertz imaging technologies are already in use in some research devices, their size, power requirements and lack of tunability usually mean they are confined to a single place and purpose.
The new superconducting chips, developed by researchers from the University of Glasgow, the University of Tsukuba and Japan’s National Institute of Advanced Industrial Science and Technology, could create lightweight, power-efficient quantum devices in the future which can be adjusted to see many terahertz fingerprints.
The chip is based around a crystal made from Bismuth Strontium Calcium Copper Oxide, or BSCCO, a high-temperature superconducting quantum material. Its unique structure produces stable and tunable coherent terahertz waves directly on a microchip, enabling compact and energy-efficient imaging systems.
In a new paper published in the journal IEEE Transactions on Applied Superconductivity, the team outline how they used the chip’s superconducting emitters to create detailed images of metallic, plant and biological materials in lab tests which demonstrate how they might be used in real-world scenarios.
The device’s potential usefulness in security applications is shown by its ability to clearly image surgical blades sealed in a paper envelope and the structural details of a floppy disk. Images of the fine details of the veins inside a dandelion leaf, and the differences between the fatty and leaner areas of a slice of pork, demonstrate how it might be used in environmental monitoring and medical applications.
The team also show how they can use the device to correctly identify fine-scale materials with high specificity. In particular, they successfully distinguish between visually similar granular substances, including salt, sugar, flour, and curry powder, based on their unique terahertz spectral signatures. This capability highlights the potential of the technology for non-invasive material identification through sealed packaging, with promising applications in security screening, pharmaceutical inspection, food quality control, and forensic analysis.
Dr Manabu Tsujimoto, of the National Institute of Advanced Industrial Science and Technology is one of the paper’s corresponding authors. He said: “Terahertz technologies have long promised transformative impact, but device limitations have prevented their wider adoption.
“Our on‑chip superconducting emitters demonstrate how innovative quantum materials can overcome these barriers. The ability to perform nondestructive imaging of plant and biological samples, as well as precise material identification, in a compact format opens exciting opportunities not only in industrial, communication, quantum, and security settings but also in medical and environmental monitoring.
“We are excited to continue refining this technology toward practical, portable, and widely accessible terahertz systems.”
Dr Kaveh Delfanazari, of the University of Glasgow’s James Watt School of Engineering, is another corresponding author of the paper. He said: “Terahertz radiation is a very powerful tool to enable the imaging and identification of a wide range of materials without harming the samples.
“Fully harnessing the potential of terahertz technologies with compact, powerful devices would enable rapid, contactless inspection of biological tissues, plant samples, and medical materials. It could also find use in healthcare diagnostics, pharmaceutical inspection, and environmental monitoring.
“Currently, our system takes about 15 minutes to create images in the lab with a 1mm resolution, so there is work to be done to make a faster, more high-resolution system. However, this paper shows clearly that that chip-scale superconducting light sources can deliver the compact electrically tunable and coherent terahertz emitters needed to bring practical miniaturised real-time imaging systems closer to reality.”
