Researchers at the University of Central Florida were able to create a 53-attosecond light pulse – the shortest pulse ever produced. Doing so broke the record of 67 attoseconds established by the team in 2012.
The achievement, reported in Nature Communications, was possible thanks to the use of an X-ray laser. Attosecond light pulses help researchers study how electrons move in molecules and could inspire the next-generation in electronic materials.
"Such attosecond soft X-rays could be used to shoot slow-motion video of electrons and atoms of biological molecules in living cells to, for instance, improve the efficiency of solar panels by better understanding how photosynthesis works," team leader Professor Zenghu Chang said in a statement.
One attosecond is a minuscule interval of time – a billionth of a billionth of a second. For context, a 53-attosecond light pulse is to a second what a second is to 600 million years.
In 53 attoseconds, light covers a distance that is less than one-thousandth of the diameter of a human hair. This speed is crucial if we want to observe electrons, which have a timescale of around 24 attoseconds.
The laser pulses act like high-speed cameras that record an action in slow-motion (think bullet flying through the air). It registers snapshots of the electrons moving, which the researchers can later stitch back together into a coherent movie.
Another important factor in the capabilities of this laser is the wavelength of the light produced. Soft X-rays are in a sweet spot when it comes to investigating the nano-world. X-ray photons are strongly absorbed by carbon atoms, but they pass through water like it’s not there. This region, called the “water window”, was the reason behind the specific set up of the laser.
"This can also be extended to condensed matter systems, allowing unprecedented accuracy and detail of atomic, molecular, and even phase, changes," said Rich Hammond, from the Army Research Office that funded the research, in a statement. "This sets the stage for many new kinds of experiments, and pushes physics forward with the ability to understand matter better than ever before."
X-ray light observations of chemical reactions is a budding field. Facilities like SLAC or XFEL are using their incredible X-ray laser to look at matter like never before. There’s a lot to learn from their analysis. Not even a year ago, we had the first close-up look at how photosynthesis actually happens. A 53-attosecond laser might take us even closer to actually seeing quantum mechanics.