A step towards safer X-rays with new detector technology

“These advances lower detection limits and pave the way for safer and more energy-efficient medical imaging and industrial monitoring,” said Omar F. Mohammed, the study’s corresponding author. “It shows that cascade-engineered devices extend the capabilities of single crystals in X-ray detection.”

Like visible light and radio waves, X-rays are a form of electromagnetic radiation. Their high energy state allows them to pass through most objects, including the soft tissues of our body. To create an X-ray, called an X-ray, the rays pass through the body and appear as shadow shapes on the image, or get stuck in denser tissues such as bones, leaving a brighter, white area. The amount of radiation a patient is exposed to during a single scan is not dangerous, and you would have to undergo thousands of scans before you would notice the compounding effects. However, this repeated exposure to high-energy radiation can damage electronic equipment or pose a risk to, for example, an X-ray technician. So the fewer rays used during a scan, the better, right?

Unfortunately, fewer rays mean a lower quality x-ray. But by increasing the sensitivity of the detector, a low dose of high-quality X-rays could theoretically be produced. That’s why Omar Mohammed and colleagues at King Abdullah University of Science and Technology have developed a device that enables these safer X-ray conditions.

To increase the sensitivity of the X-ray detector, the researchers tried to minimize the dark current – ​​the residual background noise – generated by the device. To do this, they created detectors using specialized methylammonium lead bromide perovskite crystals, and then connected the crystals in an electrical configuration known as a cascade.

The cascade configuration almost halved the dark current, improving the X-ray detection limit by five times compared to previous detectors made from the same crystals but without the cascade. X-rays taken with the new detector revealed fine details, such as a metal needle piercing a raspberry and the internal components of a USB cable. The team states that this technology is a promising method for developing foldable, safer and sensitive commercial X-ray equipment, which would serve to minimize radiation exposure during medical procedures and capture subtle details in industrial monitoring.

The authors acknowledge funding from King Abdullah University of Science and Technology (KAUST).