Building Particle Accelerators Takes More Than a Village

From magnets to power supplies, NSLS-II experts support accelerator upgrades across the Nation.

Each year, thousands of people travel far and wide to see architectural marvels such as the towering steps of the Kukulcán temple in in Chichen Itza or the intricate facade of the Cologne Cathedral in Germany. Like these marvels of history and culture, thousands of researchers travel to the U.S. Department of Energy’s (DOE’s) five light source facilities each year. They don’t come for the views, though, they come to push the boundaries of science—in fields ranging from batteries to pharmaceuticals—by using the ultrabright synchrotron light, mostly x-rays, from these facilities to conduct experiments.

This light doesn’t just appear out of nowhere. It needs to be generated by large, complex particle accelerators. And, to keep the x-rays as bright as possible, scientists and engineers are working constantly to advance them. This story highlights ongoing collaborative projects of the Accelerator Division at the National Synchrotron Light Source II (NSLS-II), located at DOE’s Brookhaven Lab.

According to historical sources, it took the Germans over 600 years to build the original Cologne Cathedral, while archeologists speculate that the Temple of Kukulcán took at least 200 years to build in two phases. Thousands of people worked on these monuments during these extremely long construction periods. This is a feat they share with modern particle accelerator projects. While the initial construction of NSLS-II took only a decade, it still involved an international effort of hundreds of people from many disciplines and professions.

From the civil engineering challenges of the building design to the construction of the hundreds of magnets inside the accelerator, it truly takes more than a village to build a particle accelerator for a synchrotron light source. Similarly, many modern accelerator projects span multiple institutions and countries to leverage the expertise in the field.

Read more on the Brookhaven National Laboratory (NBL)

Image: The photo shows a view of the National Synchrotron Light Source II (NSLS-II) accelerator tunnel located at the U.S. Department of Energy’s Office of Science Brookhaven National Laboratory.

Main Attraction: Scientists Create World’s Thinnest Magnet

The development of an ultrathin magnet that operates at room temperature could lead to new applications in computing and electronics – such as high-density, compact spintronic memory devices – and new tools for the study of quantum physics.

The ultrathin magnet, which was recently reported in the journal Nature Communications, could make big advances in next-gen memory devices, computing, spintronics, and quantum physics. It was discovered by scientists at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) and UC Berkeley.

“We’re the first to make a room-temperature 2D magnet that is chemically stable under ambient conditions,” said senior author Jie Yao, a faculty scientist in Berkeley Lab’s Materials Sciences Division and associate professor of materials science and engineering at UC Berkeley.

“This discovery is exciting because it not only makes 2D magnetism possible at room temperature, but it also uncovers a new mechanism to realize 2D magnetic materials,” added Rui Chen, a UC Berkeley graduate student in the Yao Research Group and lead author on the study.

Read more on the ALS website

Image: Illustration of magnetic coupling in a cobalt-doped zinc-oxide monolayer. Red, blue, and yellow spheres represent cobalt, oxygen, and zinc atoms, respectively.

Credit: Berkeley Lab

Dynamic, yet inertial – and definitely futuristic

Researchers conduct experiments to demonstrate inertial motion in magnetic materials

In the journal Nature Physics (DOI: 10.1038/s41567-020-01040-y), an international team of scientists from Germany, Italy, Sweden, and France report on their experimental observation of an inertial effect of electron spins in magnetic materials, which had previously been predicted, but difficult to demonstrate. The results are the outcome of one of the first long-term projects at the high-power terahertz light source TELBE at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR).

Today, most of the world’s “memory” is stored on magnetic data carriers – hard disks – without which our digital lives would be unthinkable. In the magnetic material, it is the electron spins that do the actual job of storing the data. Imagine this spin as electrons rotating around their own axes, either to the left or right – representing the digital “zeros” and “ones”.

There is something special about this rotation, as Dr. Jan-Christoph Deinert from the HZDR Institute of Radiation Physics explains: “In the magnetic field, the electron behaves like a tumbling spinning top. The rotational axis of the electron changes its direction on a circular path. We call this process precession. When disturbed by an external force, the rotational axis should also make small oscillatory movements, called nutation, which overlap the precession. Like precession, it is a characteristic of many rotating objects, from children’s spinning tops to planets like Earth. Due to its much smaller scale, however, nutation is far more difficult to observe.”

Read more on the Helzholtz Zentrum Dresden Rossendorf website

Image: An international team of scientists has managed for the first time to observe the ‘nutation’ of spins in magnetic materials (the oscillations of their axis during precession). Foto: Dunia Maccagni

An innovative mirror unit for soft X-ray beamlines at MAX IV

A new five-axis parallel kinematic mirror unit has been developed for MAX IV soft X-ray beamlines. Its development and technical characteristics are now described in a peer-reviewed article.

A new five-axis parallel kinematic mirror unit has been developed for MAX IV soft X-ray beamlines. Its development and technical characteristics are now described in a peer-reviewed article.

In an article published in March 2020 in the Journal of Synchrotron Radiation, a team from Uppsala University, MAX IV Laboratory, FMB Feinwerk und Messtechnik GmbH, and University of Tartu presents a five-axis parallel kinematic mirror unit specially developed for MAX IV soft X-ray beamlines. This new mirror unit has been created to address the unique stability requirements of 4th-generation synchrotrons such as MAX IV.

MAX IV has pioneered the development of the 4th-generation synchrotrons thanks to the implementation of the multi-bend achromat technology, a system based on the use of several sequential bending magnets in place of a single large magnet. Thanks to the introduction of this technology, the emittance has decreased by one order of magnitude, resulting in increased brightness. The multi-bend achromat system has also brought new challenges for the construction of beamlines. Decreased emittance of the storage ring has allowed for a smaller beam size, which, in turn, means higher requirements for electron beam stability, as well as for mechanical stability of the beamline components.

>Read more on the MAX IV website

Image: Veritas is one of the beamlines at MAX IV used for testing the prototype of the new five-axis parallel kinematic mirror.