An electromagnetic pulse that lasts a millionth of a second could be the key to medical imaging, communications and drug development. But this pulse, known as terahertz, requires complex and expensive equipment for long periods of time.
Now researchers at Princeton university have dramatically simplified terahertz devices: transfer the lasers and reflecting mirrors to a pair of chips that are about the size of the fingertips.
In a recent article published in the journal IEEE solid circuit, the researchers described a microchip that could produce terahertz waves. The second chip can capture and read the intricate details of the waves.
The future of electromagnetic wave: a terahertz chip that can realize the new method of perspective material
Terahertz wave is part of the electromagnetic spectrum, the electromagnetic spectrum includes wireless, X-ray and visible light, while the former is between the microwave and infrared wavelengths. Terahertz waves have some unique characteristics that attract the interest of scientists. On the one hand, they pass most of the non-conductive materials, so they can be used in safe application scenarios by packaging or extra boxes. Because they have less energy than x-rays, they do not damage human tissue or DNA.
Terahertz is also used to analyze different chemicals, which can be used to characterize specific substances, because of their different ways of working with different chemicals. This ability, known as the spectra, terahertz technology, is the most promising and challenging application using light wave analysis materials, says Sengupta.
To achieve this goal, the scientists launched a series of terahertz waves to the target objects and then observed the changes in their interactions with the wave. People's eyes are similar in the visible light range, and we see a green light reflected by the light from the chlorophyll of bin laden leaves in the green light frequency.
The challenge is how to generate a wide range of terahertz waves and explain their interaction with the target, this requires a complex array of devices, such as a bulky terahertz generator or ultra-fast laser. The size and cost of the device is impractical for most applications.
Researchers have done a lot of work to simplify these systems over the years. In September, Sengupta's team reported on a way to reduce the size and device of a terahertz generator, making it return to a chip of a millimeter size. The solution lies in the new imaging antenna function. When the terahertz wave interacts with the metal structures inside the chip, they create a complex electromagnetic field, which is unique to the incident signal. Often, these subtle areas are ignored. But the researchers realized that they could read out the pattern as a signature to determine the electromagnetic wave. The whole process can be done through tiny devices inside the microchip, which can read too much Hertz.
Daniel Mittleman, an engineering professor at brown university, says the improvement is "a very innovative work, and it has a lot of impact." Mittleman, vice President of the infrared millimeter wave international association, said that in the terahertz band, it could start to be applied to everyday life, scientists still have a lot of work to do before they can use the device, but the development is promising.