Magnetic Resonances: Freedman’s Fundamental Science Aims for Broad Impact

By Matt GolosinskiFebruary 13, 2017

There’s a quiet intensity inside Danna Freedman’s lab, a recently renovated space at Northwestern’s Technology Institute. Postdocs and grad students work with chemicals inside one of two double glove boxes, a solvent purification system, and eight tube furnaces, or else analyze materials in the PANalytical Empyrean powder x-ray diffractometer, which produces a 3-D picture of atomic and molecular structures. 

“Oh, here’s a graduate student,” says Freedman, a flicker of a smile playing across the chemist’s face as she points out a colleague working at a Mössbauer spectrometer, a tool that analyzes minute changes in energy within an atom’s nucleus. “And over here we have an undergraduate, doing something very interesting that I’ll talk to her about in a few minutes,” she adds, nodding at a colorful computer display. The on-screen representations may figure into a significant new paper that the group is preparing to submit to a high-profile journal.

It’s clear that Freedman and her team — currently totaling more than a dozen — enjoy a playful rapport that doesn’t get in the way of the serious fundamental science they are pursuing. Broadly, the group explores innovative ways to apply synthetic inorganic chemistry to address challenges in physics and energy research. Long a valuable resource for understanding biological systems, says Freedman, the discipline promises to spur advances in other areas, including quantum computing, renewable energy, and superconductivity, areas in which the Freedman Lab has projects running. As part of this effort, she and her team created an entirely new material, an iron-bismuth compound, whose properties they are studying. They hope to discover unique insights with widespread potential application.

Just outside the lab, Freedman opens a door into a small room housing two beige cabinets with a wide red stripe running down their front. A layperson might momentarily confuse the high-tech gear with a high-end office copier. “This is my baby,” she says, gesturing at the Quantum Design MPMS-XL SQUID Magnetometer that allows her to pursue another important research stream, one that also informed her undergraduate and graduate studies at Harvard, Berkeley, and MIT: magnetism and magnetic molecules.

“Within one arm of our research program, we are creating new magnets,” explains Freedman, whose deep domain expertise has earned her a prestigious early CAREER Award from the National Science Foundation; a Presidential Early Career Award for Scientists and Engineers; and a Sloan Research Fellowship, among other honors. “Magnets are a critical component in electric motors and generators, such as those at the heart of wind turbines.”

Freedman grew up in a small, upstate New York town and her demeanor retains some of the understated quality one might expect from a person whose early experiences were in a rural community. At the same time, it’s clear that Freedman has a passion for her research, a wry sense of humor, and a forthright perspective on matters outside her field as well, including politics and literature. Science and education were important touchstones for her even as a youth, when her parents nurtured her interest in discovery.

“When I was a small child I wanted to be an astronaut,” says Freedman, who joined Northwestern in 2012. “My parents prevented me from learning about the Space Shuttle Challenger explosion so I wouldn’t be scared of space travel. It didn’t take me many years, though, to realize that I would be far better suited for ground-based science.”

Still, she kept looking to the stars. In middle school, her parents brought home a town fair flyer advertising volunteer opportunities at the local Kopernik Observatory. Freedman immediately applied, earned a position, and spent several summers at the observatory — including most Friday nights. “On the rare clear night, I ran the 12-inch telescope and guided tours of constellations,” she recalls. “On other nights, I did whatever I could to help out: copying leaflets, running the cash register, etc.”

Research News visited with Freedman to learn more about her work and experiences.

It seems a long journey from your rural beginnings to Harvard, Berkeley, MIT, and now Northwestern where you’ve pursued highly technical science. How did you navigate your path?

In a sense, this question speaks to the increasingly troubling wealth distribution in our country. Decades ago, growing up in in the Southern Tier of New York would have meant proximity to the first IBM plant, a Lockheed Martin site, and a reasonably sized university, and all of the resources afforded by those organizations. Over the past couple decades, many of these industries departed. When I was a child, scientists from our local IBM came to our elementary school to show us a huge box that shot out a stream of coherent light — this was an early laser. I now carry the same device, a laser pointer, in my pocket. I volunteered in a chemistry lab at our local university when I was in high school, competed in Science Olympiad, and spent nearly every Friday night during high school volunteering or working at our observatory. I was extremely fortunate to have these opportunities, and I don’t think they are exclusive to children in large metropolitan areas.

How would you summarize your research and its potential?

We apply the fundamental ideas of inorganic chemistry to challenges in physics, particularly focusing on questions within magnetism and superconductivity. As an example, within one arm of our research program we are creating new magnets. Magnets are a critical component in electric motors and generators, such as those at the heart of wind turbines. We are pursuing a different approach to creating these magnets by combining a source of magnetic anisotropy, or preferred direction, with a source of spin. Here, we can imagine fusing the unusual properties of bismuth with the magnetic properties of iron. To create this entirely new material, we used pressures comparable to the core of Mars to produce first iron-bismuth binary compound. We are currently studying this material to uncover its magnetic or superconducting properties.

What most excites you about your work? What do you see as the potential benefits of your research?

Quite simply, we are asking questions that no one can answer. That’s the essence of all scientific discovery. Within our own research, we are seeking to understand the magnetic properties of bismuth; to find out if a certain class of materials superconducts; and to understand the effect of rapidly “flipping” nuclei on electrons. The multi-decade potential impact of generating this fundamental knowledge ranges from creating new quantum sensors, to permanent magnets, and resistance-free transport of electrons through material. This would affect our ability to generate and transport energy, and to sense small magnetic fields.

What’s the most difficult aspect of your research?

We are approaching some very large scientific problems, but every time we hit a barrier it enables us to discover new science. Those challenges are highly rewarding and one of the better parts of being a scientist. It would be pretty amazing to scale up our discovery of the first iron-bismuth binary compound, but there are a lot of other areas where I believe we can make an impact too.

How would you describe the dynamics in your lab and the importance for you of collaborating with students?

The classic image of a scientist pontificating alone at a chalkboard bears no resemblance to a modern experimental chemistry laboratory. All experimental science is accomplished through collaborative research. Within our lab, undergraduate students, graduate students, and postdoctoral fellows devise experiments, collect data, interpret data, and discover new phenomena. Working with talented, enthusiastic students is one of the highlights of academia.

How do you try to communicate the complexity and importance of your fundamental research to audiences — especially to those non-experts who may be more familiar with applied, rather than basic, research?

It’s essential to explain our scientific discoveries to the general population. The Higgs Boson is an excellent example of scientists’ successfully enthusiasm for fundamental science within the general population. The key challenge is explaining science in a way that is accurate. For example, there are many things we teach in general chemistry that are approximations. These approximations are frequently violated within real systems, to the point that the initial way we teach freshman chemistry is wrong. Explaining our research to the general public requires similar imprecise analogies. Finding the appropriate line between complete accuracy and accessibility is very difficult.

What do you see as the crucial scientific question of our time? What do you see as humanity’s most urgent challenge today?

These are two very different questions. I don’t believe science itself needs to broadly impact humanity to be transformative. Indeed, targeting scientific discovery towards immediate impact is a highly troubling current trend in our society. The classic example of separating discovery from impact is the electron. The initial discovery of the electron changed the nature of science, but did not impact humanity. Over a century later, we have an entire infrastructure built on the electron. Currently, I think understanding the composition of matter, why certain particles form and whether we can control their formation is a foundational question. An easy example is understanding the nature of superconductivity. Why do the particles intrinsic to superconductivity (Cooper pairs) form and how do we control it?

Humanity’s greatest challenges are an entirely different question, and one that perhaps I am not equipped to answer. There are many areas where science directly impacts humanity: clean water, anti-malarial drugs, control over reproduction and sexually transmitted diseases, reliable, clean sources of energy — these are all important areas where science can have a transformative impact on humanity. 

Did you ever consider another career?

I briefly considered applying to law school to work for the ACLU.