Scientists have built one of the fastest cameras that managed to film a sonic boom made of light. Using a “streak camera” the researchers of Washington University in St. Louis have recorded these photonic shockwaves, which calculates both the temporal data and the image at 100 billion frames per second. Their research has been published in the journal Science Advances.
The team shot 7 picoseconds long green laser pulses through a tunnel full of dry fog that was placed between plates made from silicone rubber and aluminum oxide. As the light travels 30 percent faster than the light in the plate, it created a sort of sonic boom when the light from the air into the plate.
“You can think of the laser source as the supersonic jet and everything is dragged behind. Instead of generating a sound, we’re generating a scattered wavelet,” says Jinyang Liang, a postdoctoral research associate in Lihong Wang’s Optical Imaging Lab at Washington University, in St. Louis.
The camera is particularly important to film the light in real time. The custom-built camera only needs one exposure while other techniques require many exposures. Besides, it allows you to capture events that are not even repetitive, like the laser pulses.
This experiment could provide new understanding into light. However, the researchers are more interested in using this technology to track neurons as the system is quite fast. Besides, it could be used to track small details, which would improve the understanding of both the brain and mind-related issues.