Scientists from ITMO University have created a cheap and easy-to-manufacture, highly sensitive and fast-acting terahertz radiation sensor (detector) based on thermoelectric films.
The developers are confident that the invention will find application in the field of defense, medicine, IT and other areas.
The results of the research, supported by the Russian Science Foundation, are published in the journal Photonics.
This was reported to RT by the press service of the university.
The development of the Russian team is thin thermoelectric films based on bismuth (Bi) with different concentrations of antimony (Sb), which are distinguished by increased sensitivity to terahertz radiation.
As the researchers note, the terahertz range remains insufficiently studied, and there are almost no good devices that would work in it.
The main difficulty in the work, the scientists called the solution to the problem of the sensitivity of the sensors, since at room temperature the high-frequency region of terahertz radiation also accounts for the thermal radiation of objects, which makes it very difficult to separate one from the other.
“The existing detectors are based on measuring the thermal excitation of the surface.
Despite many recent advances in terahertz sensor technology, the fastest of them have low sensitivity, and the most sensitive tend to be slow, ”explained Mikhail Khodzitsky, one of the study authors, head of the terahertz biomedicine laboratory at the Faculty of Energy and Ecotechnology at ITMO University.
“One of the main tasks of this research is the search for new thermoelectric materials with high sensitivity to terahertz radiation at room temperature.
Then you don't have to use expensive and complicated cooling equipment, ”he added.
The invention is claimed as a compact and inexpensive alternative to existing sensors.
The resulting terahertz detector operates rather quickly: the response time is less than ten millionths of a second.
Installation diagram
© Mikhail Khodzitsky / ITMO University
Adjusting such sensors to the required detection frequency opens up the possibility of using them in different ranges.
It is noted that the development will be useful for new generation wireless communication devices, which are based on the transmission of terahertz signals (in particular, using terahertz waves can increase the data transfer rate in WiFi systems).
According to scientists, the development can have a much wider range of practical applications - from biomedicine to security systems, since terahertz radiation has a unique ability to penetrate many materials and receive their special "spectral portrait" through an obstacle (for example, in the form of paper or plastic packaging ).
So, with the help of new sensors, it becomes possible to find harmful or prohibited substances in postal envelopes or contraband in luggage.
The researchers also call the field of medical diagnostics promising for the application of this technology. Unlike X-ray radiation, terahertz radiation is not ionizing, and therefore can be used without harm to the patient's body, for example, to search for cancerous tumors.