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 pioneer method that enables material to carry more electrical current without resistance at a higher temperature.

Discovering previously unobserved quantum states nested inside the quantum Hall effect in a single-layer form of carbon known as graphene, researchers have found evidence of a new state of matter that challenges scientists' understanding of collective electron behavior.

A scientist combines high magnetic fields with ultra short laser pulses to probe the mysteries of photosynthesis.

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.

Niobium diselenide is found to retain its superconductivity even under very high magnetic fields.

This week at the lab, we retired a 1990 Toyota and are parking a 2016 Mercedes in its spot.

That's the metaphor offered by Bryon Dalton, head of operations for the lab's DC Field Facility, for a big upgrade of the lab's world-record 45 tesla hybrid magnet: a new set of 3,500-pound vacuum pumps.

Good-bye roll-down windows and Bush Sr.-era fuel economy. Hello turn-by-turn navigation, Bluetooth wireless data link and 10-way power driver seat.

The $260,000 German-made vacuum pumps will improve reliability and performance, generate systems diagnostics, and allow staff to run the pumps remotely. "You're going to have a better feel for what's going on and better control over it," said Dalton.

The pumps play a critical role in the operation of the hybrid, which pairs a resistive magnet with a superconducting magnet of niobium-tin and niobium titanium that requires temperatures near absolute zero. Helium liquefied on site has a temperature of 4.7 Kelvin, making Plutonian weather seem tropical by comparison. By dropping that liquid helium to below atmospheric pressure, the vacuum pumps, used with a special cooling apparatus called a Joules-Thompson refrigerator, gets it down to 1.6 Kelvin. This turns it into a zero-viscosity "superfluid" and maximizes the hybrid's efficiency.


Photo by Stephen Bilenky, text by Kristen Coyne.

This modest-looking tank is a MagLab hero in disguise.

Nicolas Doiron-Leyraud of Canada's Université de Sherbrooke talks about his recent experiments on cuprate superconductors, why he chose physics over philosophy, and what makes the MagLab a great place to do science.

This week at the lab is pretty quiet. Most of the staff is off for the holidays.

But not Jesus Torres Camacho and Dan Freeman — because science never sleeps.

As we head into the first, and statistically coldest, month of the year (at least in Florida), Camacho and Freeman will be at the MagLab doing their part to keep things frosty.

The pair are members of the MagLab’s cryogenics team, making sure the lab’s scientists and magnets have enough liquid helium and liquid nitrogen to keep the experiments going. All the lab’s superconducting magnets require cryogens, as do many of the experiments run here: Scientists doing low-temperature physics often want to put their samples in a deep freeze (temperatures often just above absolute zero) in order to observe special phenomena. The lab uses about 435,000 liters (114,915 gallons) of liquid helium a year (much of which is recycled), and about four times as much liquid nitrogen.

That's where the cryogenics team comes in, converting helium from gas to a frigid liquid with our helium liquefier and helping distribute it across the 370,000-square-foot lab through an army of some 55 dewars — basically Thermoses on steroids and wheels — containing 100 to 500 liters (26 to 132 gallons) of the stuff.

On an average day, about a dozen scientists, technicians, postdocs or graduate students come to the lab’s "helium retrieval station," located in the DC Field Facility, to pick up a newly refilled stainless steel dewar, and wheel it through the hallways back to their experiments and instruments. It works out to about 1,200 liters (317 gallons) of helium a day.


Text by Kristen Coyne

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