World's most powerful X-ray laser fired for the first time
The US Department of Energy's (DOE) SLAC National Accelerator Laboratory has fired the first X-rays using the upgraded Linac Coherent Light Source (LCLS) X-ray free-electron laser (XFEL), a press release said. The upgraded version, dubbed LCLS-II, was built for $1.1 billion.
The SLAC National Accelerator Laboratory at Stanford has been building and operating powerful tools for advancing science for over six decades. The original LCLS was the world's first XFEL, reaching its first light in April 2009.
Even as X-rays have become a routine application in healthcare, scientists continue to use much more powerful versions to probe materials and biological materials to understand them better. The original LCLS accelerated electrons through a room-temperature copper pipe, limiting it to 120 X-ray pulses per second.
The upgrade, which took over a decade, makes the LCLS-II 8,000 times faster as it can generate nearly a million X-ray flashes per second, which are more powerful than anything we have seen before.
How does LCLS-II work?
The LCLS-II's enhanced capabilities are thanks to the superconducting accelerator built to fire the X-rays. The accelerator consists of 37 modules that can cool down helium to -456 degrees Fahrenheit (-271 degrees Celsius), just a notch above absolute zero. At these temperatures, the accelerator increases electrons to high energy states with nearly zero energy losses.
The SLAC team has retained the original copper pipe accelerator, allowing for data collection over a wide energy range and gathering more data in less time while also broadening the scope of experiments that can be carried out at the facility.
In addition to a new electron source, the LCLS-II has also seen the addition of two new undulators that can generate X-rays from the electron beams. Dubbed "soft" and "hard", these undulators produce low- and high-energy X-rays, allowing researchers to carry out their experiments with much higher precision and the option to probe deeper.
What can the LCLS-II do?
The LCLS was instrumental in creating the first "molecular movie" for studying complex chemical processes and watching how plants and algae absorb sunlight to give us oxygen in real time. The X-rays from the instrument also shed light on how planets evolve and how diamond rains are formed.
Now, with an even more powerful setup, the LCLS-II is poised to take on challenges considered out of reach. Researchers will now be able to study quantum materials in greater detail, paving the way for building more efficient quantum devices, computers, and ultra-fast data processing, the press release said.
The LCLS-II will also enable researchers to capture snapshots of chemical reactions at an atomic scale and help design more efficient processes in industries such as chemical production as well as energy generation and help in the reduction of greenhouse gases.
"Experiments in each of these areas are set to begin in the coming weeks and months, attracting thousands of researchers from across the nation and worldwide,” said LCLS Director Mike Dunne in the press release. “DOE user facilities such as LCLS are provided at no cost to the users – we select based on the most important and impactful science. LCLS-II is going to drive a revolution across many academic and industrial sectors."