In a well-run library, an authoritative "Sssshhhh!!" will quiet things down in a jiffy.
At the MagLab, we value our quiet time, too — especially in the Millikelvin Facility, home to some of our most sensitive equipment and experiments. But we need more than a pursed-lipped librarian: We need a building designed from top to bottom to shield its magnets from the noise of external electromagnetic (EM) radiation.
And we're about to get it. We recently broke ground on an extension to the existing Millikelvin Facility, currently home to three superconducting magnets that scientists use for experiments at ultra-low temperatures.
The 1,640-square-foot addition will house two new superconducting magnets, including the much-anticipated 32 tesla all-superconducting magnet. Designed and built at the MagLab, the 32 T will shatter existing records for field strength in superconducting magnets when it comes online later this year.
The design of the $1.2-million Millikelvin addition reflects the many lessons learned from two decades operating the existing facility, said MagLab Facility Director John Kynoch. The walls of the windowless structure will include a layer of copper, effectively creating an EM radiation-blocking Faraday cage. The magnets will be positioned safely below ground, surrounded by concrete reinforced with non-magnetic rebar. The extension's high-quality electrical grounds will be separate from the main building.
Even the LED lighting and air conditioning are designed to minimize noise, air currents and temperature fluctuations that could disturb finicky experiments, said Tim Murphy, who oversees Millikelvin as director of the DC Field Facility.
"If your building temperature swings wildly," said Murphy, "you can see that in your data."
Years in the planning, the addition is designed not just to house magnets, but to do science.
"We're treating the building as part of the instrument," said Murphy, "not just some place you put the instrument."
The new building is slated for completion in the spring of 2017.
Text by Kristen Coyne. Photo by Stephen Bilenky.
Scientists have discovered a way to significantly improve the performance of a decades-old superconductor, promising future applications for particle accelerators and research magnets.
This week at the lab, we're trying a magnet on for size.
A research magnet is made of a set of coils engineered from a current-carrying material — a fancy version of the electromagnet many kids make in school using a wire, battery and nail. Typically, four or five coils are slid one inside the next like Russian nesting dolls.
This week, we're slipping the second coil of the highly anticipated 32 tesla all superconducting magnet over the inner-most coil, then making any necessary adjustments. Like a good pair of jeans, the fit should be snug but not tight, with a mere millimeter between the two coils.
"Assembling the coils and the entire electrical circuit is an intricate job, and an exiting one," said project leader Huub Weijers. "After almost seven years of development, design, testing and construction of components, the final magnet is taking shape in front of our eyes."
These two coils, which contain about 6 miles of superconducting tape made of the novel, high-temperature superconductor yttrium barium copper oxide (YBCO). But YBCO is only one layer in this magnet. Those coils will soon be nested inside five more of coils made of conventional superconductors, three of niobium-tin and two of niobium-titanium.
The finished, 2.3-ton magnet system, when completed this summer, will join the MagLab’s roster of world-record magnets. At 32 tesla, it will be by far the strongest superconducting user magnet in the world, surpassing the current record of 23.5 tesla.
"It’s a difficult task to work through the many details of a new technology," said the magnet's lead designer Adam Voran, who managed the computer modeling for the project. "But the reward of seeing those meticulous designs being born into a tangible reality is exhilarating."
Photo by Stephen Bilenky / Text by Kristen Coyne.
This week at the lab, Peng Chen starts a new job at the Applied Superconductivity Center (ASC), where he will contribute to developing a groundbreaking magnet with bismuth-strontium-calcium-copper-oxide (Bi-2212), a promising high-temperature superconductor.
Chen's new job sounds a lot like his old job: building a groundbreaking magnet at the ASC with Bi-2212. The main difference is that last week, Chen was still a graduate research assistant. This week, he is a postdoctoral research associate, having graduated Saturday from Florida State University (FSU) with a Ph.D. in mechanical engineering.
"I can relax a little bit," laughed Chen, who has put in long hours over the past several months writing and revising his thesis.
In addition to designing and building world-record magnets used by scientists from across the globe, the MagLab has an important educational mission. This includes training early-career scientists like Chen. It's not by accident that undergraduates, graduate students and postdocs make up 40 percent of the lab's staff.
Since arriving here from China five years ago, Chen has experienced an intense, hands-on education among the team building a Bi-2212-based, high-field, high-homogeneity nuclear magnetic resonance magnet dubbed the Platypus. ASC Director David Larbalestier, who is Chen's advisor, said Chen has shown a lot of grit in the face of tough technical problems that come with building a first-of-its-kind instrument. In fact, ASC is hoping to get a patent out of a fully superconducting joint Chen built for the Platypus.
"He combines an engineering viewpoint with a strong desire to understand what he is doing, which makes his approach to complex technical problems very valuable," said Larbalestier, who placed the blue doctoral hood on Chen during his graduation ceremony to signify his former student’s new status.
Chen said he is looking forward to his new role on the team.
"In the transition from student to postdoc, you have more freedom," said Chen. "It's not only about your dissertation; you have more choices to do different aspects of the project and to collaborate with other teammates to support them — take more responsibility. I have a feeling I will do more and broaden my duties."
Text by Kristen Coyne / Photo courtesy of Peng Chen.
Using a novel method of winding the magnet coil that dispensed with the traditional insulation, the MagLab reached another world record and laid the foundation for more to come.
No insulation? No problem! In fact, by challenging the conventions of magnet making, MagLab engineers created a first-of-its-kind magnet that has only just begun to make records.
Tapping into MagLab expertise on superconductors and cryogenics, a research team built a novel neutron scattering device that is more efficient and produces better data than previous techniques.
A new type of superconducting cable was successfully tested at high field at the MagLab, opening the door for the next generation of accelerator magnets operating at 20 teslas (T) and above.
New calculations that reveal the workings of a new type of high-field research magnet will aid in future magnet designs.
One of the best tools for testing new materials for the next generation of research magnets is a MagLab magnet.