Pushing the Frontier of Extreme Light-Matter Interaction Research

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Category: Research News

Published: Monday, February 08 2021 05:33

University of Maryland Physics Professor Howard Milchberg and the students and postdoctoral researchers in his lab explore the dramatic results of experiments that push light to extremes in the presence of matter. In Milchberg’s opinion, researching the intense interactions between light and matter—which are only possible thanks to the revolutionary technology of lasers—brings together the most interesting aspects of physics.

“Once you considered the effect that an intense laser beam has on matter, the number of basic physics and application areas exploded,” said Milchberg, who also holds appointments in the Department of Electrical and Computer Engineering and the Institute for Research in Electronics and Applied Physics. “And understanding the interaction between intense light and matter requires bringing in tools from all areas of physics. It flexes all your physics muscles, experimental and theoretical, and it overlaps with all of the major areas. You have to deal with atomic physics, plasma physics, condensed matter physics, high-pressure physics and quantum physics. It is intellectually challenging and, as a bonus, it has many practical applications.”

In explorinIntense Laser-Matter Interactions Lab, University of Marylandg this research topic, his lab has discovered new physics and technological opportunities. From cutting-edge, powerful laser pulses to vortices made of light, recent research from Milchberg’s lab keeps revealing new ways that light and matter can come together and deliver new results.

The richness of this line of research comes from the fact that light is much more than just illumination traveling in straight lines at a constant speed. It is energy that can dance intricately as it travels and can interact with matter in exotic ways—including tearing atoms into pieces.

Light is traveling electric and magnetic energy, and it is often convenient to visualize light as traveling waves in the electric and magnetic fields. The hills and troughs in the waves represent the shifting of the strength and direction of the fields that push and pull on charged particles, like the protons and electrons that make up atoms. Powerful lasers can even accelerate charged particles to near the speed of light where the unusual behaviors described by Einstein’s theory of relativity come into play.

Milchberg’s lab often investigates the dramatic results of dialing a laser up to extreme strengths where it exceeds the field that connects the cores of atoms to its electrons. As researchers like Milchberg push lasers to greater and greater power levels, they reach a roadblock: A laser tends to spread its power out over an increasing area as it travels, and a laser with enough power will vaporize any solid piece of equipment that researchers try to use to corral it.

So an optical fiber, like those that commonly carry internet signals, are useless when faced with a powerful research laser. The central core and outer cladding that make up the fiber get destroyed without any chance to keep the light concentrated as it blazes forward.

But Milchberg’s research has uncovered multiple ways to use the interactions of light with matter to keep powerful laser beams contained. In papers published in the journals Physical Review Letters and Physical Review Research over the past year, Milchberg and his colleagues described two new ways to keep intense laser beams contained in a way that can accelerate particles and produce advanced coherent light sources. In addition to improving our understanding of how light and matter interact, the techniques might be implemented as tools for research in other areas, like high-energy physics, and for use in industrial and medical settings.Researchers have generated vortices of light that they describe as “edge-first flying donuts” and developed a new technique for imaging them in mid-flight. (Credit: Scott Hancock/University of Maryland)

In these projects, the group used its expertise to give the technology of optical fibers an extreme indestructible makeover. The key lies in building the waveguides—devices such as optical fibers that transport waves down a confined path—out of a material that has already been vaporized. The team forms the material—an energetic state of matter called a plasma—by letting a laser rip electrons free from their atoms to form a cloud of charged particles.

“A plasma waveguide has all the structure of an optical fiber, the classic core, the classic cladding,” Milchberg said. “Although in this case, it's indestructible. The hydrogen plasma forming the waveguide is already ripped up into its protons and electrons, so there's not much more violence you can do to it.”

For the first project, the group used two laser pulses: a solid beam and then a hollow tube of light matching the desired form of the outer shell. These two lasers allowed the team to independently craft the low-density cores and outer shells more carefully than previous approaches. This refined control improved the amount of power the techniques could concentrate and the distance the powerful pulses could travel­­­­­—a key to achieving desired levels of acceleration with a compact system.

The second approach produced a similar plasma waveguide but sacrificed the ability to tailor the resulting waveguide in favor of using a simpler, more accessible technique. In this technique, the researchers created a tube of low-density gas and then relied on the front edge of the powerful pulse to rip the electrons free and create the waveguide structure on-the-fly.

“It's actually simpler than the first method,” Milchberg said. “But there's less control. And we did an analysis which shows that if you want to have big diameter waveguides, the first method is actually more efficient than the second method.”

Both methods have potential uses as laser accelerators that can generate bursts of electrons of energy 10 billion electron volts, and Milchberg’s group is already doing those experiments.

In addition to these two techniques, Milchberg’s group is developing a technique that uses a 1,000 times higher density hydrogen gas to accelerate electrons without constructing a waveguide, while using 1,000 times less laser energy. This new technique improves on established methods by avoiding negative effects from the light vibrating the electrons as they get accelerated behind the intense laser pulse.

To do this, they used pulses of circularly polarized light that aren’t even as long as two full lengths of the waves of the light that is used. The field of circularly polarized light rotates as the light travels and this variation cancels out the effect of the asymmetries of the vibration from the light waves, enabling electron beams of higher quality than previous attempts. The denser gas used in this approach isn’t compatible with the 10 billion electron volt energies of the other approaches, but the technique might have its own niche to fill.

“Our experiments have spanned the higher through lower energy ends of laser-based acceleration,” Milchberg said. “The plasma waveguide effort is aimed at 10 billion electron volts, which is of high energy physics interest, while the newer research using millijoule pulses and dense hydrogen generates 15 million electron volts.  Although a high energy, it isn’t enough for high energy physics. But the energy is more than sufficient to do time-resolved medical imaging and materials imaging.”

But accelerating particles is not the only aspect of light-matter interactions that Milchberg’s group investigates. For instance, they also discovered new intricate effects that can be created in light pulses.

In a paper published in the journal Optica in December 2019, they generated and observed a new kind of light structure called a spatiotemporal optical vortex (STOV). STOVs are whorls in the way the phase—the property of light and other waves that tells you are where you are on the wave—changes in space and time. The researchers had to first develop a method to create these vortices and then figure out how to observe them in flight. The observation required analysis of the interaction between the STOVs and another bit of light while traveling through a thin glass window.

Understanding STOVs provides insight into how light produces the high-intensity laser effect called self-guiding. Milchberg’s team had previously discovered a naturally occurring form of STOV that behave like “optical smoke rings” and are crucial for all self-guiding processes. These vortices may also have applications in transmitting information because the twisting structure tends to stabilize itself by filling any sections that get knocked out—say by water droplets in the air that the signal travels through.

All of these research results represent new techniques that may be useful tools for researchers and industry, and they deepen our understanding of the intricate back-and-forth that can be engineered between light and matter.

“One of the things that I would say my group is known for is that all of our papers include theory and simulation that accompanies the experiments,” Milchberg said. “And that has provided an important feedback loop to guide and refine the experiments.”

Milchberg credits his group’s steady generation of new discoveries to his graduate students.

“I don't think I could have done any of this in a non-university setting,” Milchberg said. “I think the sort of relationship one has with students and they have with each other where we're all batting ideas back-and-forth and having a continuous free-for-all discussion—with crazy thoughts encouraged—is not the same as in a place filled with longtime Ph.D.s and an established hierarchy. The freedom to ask naïve questions and argue a lot is essential.”

Written by Bailey Bedford

Making the Very Difficult to Understand Easy to Understand

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Category: Department News

Published: Sunday, February 07 2021 05:38

Alan Henry is a respected tech writer at Wired who also worked for PC Magazine, Lifehacker, and even The New York Times, making his mark as a journalist covering technology and science. But years ago, long before Henry began writing articles to help people understand the role of technology in their lives—or even thinking about becoming a journalist—his sights were set on a different life mission entirely.

“When I was a child, I insisted that I was gonna be an astronaut,” Henry explained. “I always knew I was going to study space science. I wanted to be an astronomer. My parents gave me books about the stars and the planets and telescopes and the space shuttle program. I had press photos of astronauts from NASA on my wall the same way that other kids would have superheroes. That’s kind of how I was.”

In 1997, when Henry came to the University of Maryland for college, his heart was still set on a career in space. And he knew studying physics and astronomy would help get him thereAlan Henry.

“By then, I didn’t necessarily want to be a professional astronaut, but as I was studying physics and astronomy at UMD, I kept thinking about what it would be like to essentially run an observatory in space,” Henry said. “And I was like, that’s the future I want to work towards. I want to be a scientist who’s based on the moon and I want my telescope on the moon and that’s what I want to do with my life.”

But during Henry’s time at Maryland, things happened that began to change his thinking. He started working as a tech for UMD’s Division of IT and he took advantage of an opportunity to redesign the Department of Astronomy’s website. And after three years working as a resident assistant, he discovered an unexpected passion for video games.

“Some of my residents, people I was supposed to be supervising, they were super into video games,” Henry recalled. “I would sit in their room and just watch them play video games because I thought it was the most enchanting thing to look at. I just fell in love with video games. Up to that point, the only purpose the computer in my room had was to write papers.”

More and more, Henry found himself connecting with technology and enjoying it. And his plans for the future began to change.

“I decided maybe technology was my way to help not just everyone around me, but especially the scientists around me, do better work,” he said. “Maybe technology’s the place where my talents are best served.”

By the time Henry graduated from Maryland in 2002, he’d found a comfortable place in the world of tech. He went from working at the help desk at UMD to a challenging new position working with the National Institutes of Health.

“I was working for a contractor that had the tech contract for the National Cancer Institute,” Henry explained. “My entire job was working alongside scientists and making sure their technology needs were met, and it was an extremely rewarding job. Eventually I kind of grew out of crawling under desks and fixing computers, so I decided I wanted to do more in that field.”

In 2003, Henry went back to school at what is now called University of Maryland Global Campus to get an MBA, and then he became a project manager for Merkle, a data-driven customer experience management company in Columbia, Maryland. In his spare time, he started to write.

“The blogging craze was starting up on the internet,” Henry recalled. “People were talking about their love of technology and their love of science and the things they were passionate about. I started my own little blog about gadgets and tech and science.”

In 2006, that “little blog” led to Henry’s first real writing opportunity.

“An editor at PC Magazine reached out and said, ‘Hey, you seem to be able to communicate with people, you seem to have some interest in this, do you want to write for us?’ And I said, ‘Sure,’” Henry explained.

It was just a part-time writing gig at first, but Henry quickly realized he’d found his niche.

“It was a kind of side hustle that got me thinking about using the skills that I learned up to this point to communicate these complex ideas in tangible and understandable ways,” Henry said. “And readers could kind of take away and kind of feel more literate and feel more informed without necessarily talking down to them. And that’s kind of how I made the switch from tech to journalism.”

Freelancing at PC Magazine led to a job as an editor at Lifehacker, where Henry spent several years spearheading much of the site’s science-forward coverage and was eventually named editor-in-chief. When Lifehacker’s parent company, Gawker, went bankrupt, it set the stage for Henry’s next move.

“I had a friend at The New York Times who had been a big fan of Lifehacker and he decided they wanted that kind of energy so he just pulled me over,” Henry explained. “And I was at The New York Times for 3 or 4 years working on the Smarter Living project. Smarter Living was designed to do two things: Publish great service journalism that helped The Times’ readers make tangible improvements to their lives but didn’t necessarily fit with a specific section or area of coverage that The Times already had and also to work across the entire paper to show other editors that service journalism should be core to their beats. From politics to climate, people want to know how that news affects them, and what they can do or learn that will help them be more informed, active and fulfilled.”

In April 2020, Henry went to work for Wired, recruited by the web editor, a colleague from Henry’s Gawker days who made him an offer he couldn’t refuse.

“He reached out to me and said, ‘We really want to do this thing that you’ve always been interested in, which is distilling complicated technology, complicated science, complicated kind of forward-thinking futurism down in a way that people feel they can relate to’ and he gave me a great opportunity to kind of build something new here,” Henry recalled.

For Henry, the service editor position at Wired, which also involves writing regularly about video games, fits perfectly with the kind of journalism he enjoys most—stories that teach people about the role of technology in their daily lives.

“Whether it’s a tangible benefit that a reader can get out of reading a piece like how to fix my computer fast, or how to find music and audiobooks to listen to fast, or we have all this great information about the COVID-19 pandemic, how do we distill this into something that a reader can look at and act on, these are the kinds of stories I like to write,” he explained.

And though Henry jokingly describes himself as a “recovering physicist,” the knowledge he gained studying physics at UMD is at the foundation of everything he does.

“There is something uniquely important about having a basic understanding of not just the physical world, but basic training in science that kind of shapes your perceptions of things around you,” Henry observed. “You can take the kid out of physics, but you can’t take physics out of the kid. My training in physics teaches me that these complex topics that people think are intractable are not that at all. You just need to break them down to poke and prod and examine them until we find things that we do understand that will kind of give us a string that we can use to unravel the rest.”

Last year, Henry took on something new—writing his first book, based on an article he wrote for The New York Times.

“It’s tentatively titled Productivity Without Privilege. The book is supposed to be an examination of productivity tips and tricks for people who are otherwise normally marginalized in the workplace,” Henry explained. “It was inspired in some ways by my own experiences where I would meet people and also work around people who were judged differently—not based on talent, but based on who they were, sometimes their ethnic background, a lot of times their class background or race or gender.”

More than just his own experiences, in many ways the book was inspired by what he saw going on in the world around him.

“When I looked around and I saw the #MeToo movement and I saw people speaking out about the conditions at their workplaces, I thought this is the time to do this,” Henry said. “And luckily, I had a wonderful editor at Random House who reached out to me after the article and said, ‘We want to make this a book.’ Really writing the book is my next big challenge.”

Now living in New York, Henry enjoys exploring the city when he has the chance and still loves playing video games as much as he did in college. And on the weekends, it’s a good bet you’ll find him in the kitchen.

“One thing people don’t know about me is exactly how much I love to cook,” Henry said. “I don’t talk too much about it because when you work side by side with people like Sam Sifton, the food editor of The New York Times, you don’t really think too much of your own cooking expertise, but I will spend hours on the weekend just poking and prodding the perfect roast. As much as I’m into physics and tech journalism, I’m also extremely into cooking. Cooking’s still science; it’s just science from a different perspective.”

For Henry, seeing science from a different perspective has fueled a successful, and sometimes unexpected, career path for nearly 20 years. What’s next?

“I’ve had so many moments when I thought my career peaked and there was nowhere for me to go that it’s hard for me to even answer that question,” Henry said. “I thought I was at a peak when I was chief of a website, I thought I was at a career peak when I was at The New York Times, and now working at Wired as well. I’ve kind of made it my mission to help people understand complicated topics, especially when it comes to technology and science. I definitely just want to continue that—making the very difficult to understand easy to understand.”

Written by Leslie Miller

Senior Jorge Ramirez is Passionate About Inspiring Future Latinx Physicists

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Category: Department News

Published: Sunday, February 07 2021 05:36

 As a child of immigrant parents, Jorge Ramirez learned very early on the importance of education. And not just any education—a U.S. education.Jorge Ramirez Ortiz

“My family was heavily burdened by the economic crises happening in Honduras during the ’90s, so my parents immigrated to the United States with my siblings and me,” he shared. “My parents were illegal immigrants my entire life, so despite having college experience and a lot of skills, they were deemed not worthy in the U.S. Seeing my parents having to work menial labor jobs despite all of their skills made me dead set on getting a U.S. education.”

Ramirez, a senior physics major at the University of Maryland, developed an interest in science at an early age. He participated in the Science Bowl—a weekly game show hosted by the Prince George’s County Public Schools where students from different schools compete against each other to test their science IQ—for the first time when he was in fifth grade. In sixth grade, he competed again and won, which solidified his love for science. When he went to high school, he began to focus on physics.

“When I was a senior in high school, I was a part of an internship program where I met my current mentor, [UMD Physics Professor] Dan Lathrop,” Ramirez said. “During that internship, I had my first research experience and I designed my own experiment where I identified the resonant modes of suspension bridge cables of a bridge near the Baltimore Harbor. It was my first experience in academia that helped me realize that I liked doing experimental design and data analysis.”

Part of what Ramirez loves about physics is that it provides a foundation for so many things, and it is knowledge that he’ll always be able to use in his day-to-day life. 

“Physics is the foundation for everything, so if I ever have an interest in another field, I can build on my foundations of physics,” he said. “Knowing physics means that I can learn anything else as long as I work with my roots. And if I ever end up in a situation like my parents where my degree isn’t accepted, everything that I know about physics is real and I can assert that no matter what.”

Helping others see themselves in the world of physics is one of the things Ramirez is most passionate about. That’s why he’s a member of the Department of Physics’ Climate Committee, which launched last year to ensure that the department is welcoming to everyone, and why he serves as the president of the Society of Physics Students, which aims to help physics students and those interested in physics connect with one another.

He is also working on a very special multimedia project called Rostros Físicos, which is aimed directly at the Latinx community. Led by Daniel Serrano, who works in UMD’s Institute for Research in Electronics and Applied Physics as a senior faculty specialist, the project is a video series that focuses on the experiences, backgrounds and expertise of Latinx physicists from all stages of the academic path.

“The point of Rostros Físicos is to create a platform in which Hispanic and Latinx-identifying physicists can not only give an example of their work and serve as role models, but also explore their backgrounds and their perceptions of physics, where they came from and how they got to where they are,” Ramirez said. “We made Rostros Físicos to be a resource for the future generation to say, ‘Okay, this person looks like me, sounds like me, has a similar upbringing to me, and is a successful physicist, so I think I can be one, too.’” 

In January 2021, when the Department of Physics and the National Institute of Standards and Technology hosted the Conference for Undergraduate Underrepresented Minorities in Physics, Ramirez and Serrano had the opportunity to host a workshop and show video clips from Rostros Físicos. They engaged in a discussion about the videos and how the representation of Latinx physicist role models can impact the future of the field.

“The people at the workshop were jumping at the opportunity to discuss what they saw during the videos and tie it into what they learned during other panels at the conference about representation in physics,” Ramirez said. “Everyone involved with the workshop was super happy with the feedback that we received and the impact that we had. I'm really glad we had the opportunity to be a part of it.”

In the future, Ramirez and Serrano hope to expand Rostros Físicos into a database where people who are interested in Latinx physicists can easily look up all of the people in the project and learn more about them.

As far as Ramirez’s personal future goes, inspiring other Latinx people to become physicists is at the center of his goals. He is currently applying to graduate schools to study quantum information and quantum computing, and he hopes to eventually become a professor. 

“I want to be a professor because, frankly, there are not very many Latinx professors,” he said. “I want the ability to inspire Latinx students by saying, ‘I grew up in the exact same situation as you and now I'm a professor of physics, so you can do it too.’” 

Written by Chelsea Torres

Taking on Climate Change

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Category: Department News

Published: Sunday, February 07 2021 05:13

Ellen Williams is an optimist. And she believes in the power of science and technology to help society solve grand challenges, like transitioning to clean energy and combating climate change. Williams, a Distinguished University Professor in the University of Maryland’s Department of Physics and Institute for Physical Science and Technology, approaches these challenges with a broader scope of experience than most.

In addition to spending over 30 years conducting research and teaching at UMD, Williams also served as chief scientist for British Petroleum (BP), as director of the U.S. Advanced Research Projects Agency-Energy (ARPA-E), and as a member of the Congressional Commission on the Strategic Posture of the United States, which was created to make recommendations on critical issues related to the country’s nuclear strategy.

In July 2020, Williams took on a new challenge—she began a five-year term as director of UMD’s Earth System Science Interdisciplinary Center (ESSIC).

The twists and turns in her career are testament to the power of hard work and a fearless approach to new opportunities. Williams filled roles she didn’t even know to dream about as a child growing up in the suburbs of Detroit.

“I didn't really understand what a scientist did or what it would mean to be a scientist,” Williams said about her career ambitions in high school. “But I enjoyed my chemistry classes, and I thought, ‘Well, I can major in chemistry and I can always go to med school because I know what a doctor does.’”

That backup plan turned out to be unnecessary. By the time she earned her bachelor's degree in chemistry from Michigan State University in 1976, Williams discovered an affinity for thermodynamics and statistical mechanics, and she learned there was a path for someone like her, someone who enjoyed research. 

“I was very interested in this quantification of how molecules and atoms move around and behave themselves or don't, as the case may be,” she said. “I did research through my entire undergraduate career, and I just had a sense that there was lots of opportunity and lots of interesting things there. When someone said, ‘You know you can go to graduate school for this,’ I realized there was a pathway, and if others were doing it, I could do it.” 

It was a time when not many women pursued research careers in chemistry, but looking back, Williams never really felt the gender gap. She was one of an unusually large cohort of women pursuing graduate degrees in chemistry at the California Institute of Technology, so she always felt supported. And her professors encouraged her to follow her interests. 

Looking back, she may also have been more prepared than many to take on a highly technical field thanks to her father’s enthusiasm for the new technology of the time. An engineer for a car manufacturer in Detroit, Williams’ father was an early adopter of computers, and he encouraged her to take a computer science class during her senior year of high school. This was in the 1960s, the days of punch cards and room-sized mainframe computers. And although the class didn’t spark a particular interest in computer science as a career, it afforded Williams a familiarity with data and computing that would later help with her scientific research. 

“I wasn’t afraid of data processing and computers, because I started out with some rudimentary computer skills already,” she said. “I’ve watched computing evolve and become a more and more important and powerful part of research, and having some computer skills in the beginning just meant I was ready to jump in.”

At Caltech, Williams continued her research in thermodynamics and statistical mechanics, earning a Ph.D. in chemistry in 1981. She joined UMD that same year as a postdoctoral fellow and rose through the ranks to become a professor in 1991. 

“My research focus was really about understanding how you can go from the properties of individual atoms and molecules to understanding how they behave in the macroscopic world, which turns out to be a totally nontrivial problem,” she said. 

Nontrivial indeed. Those questions remained her central focus for the next few decades, propelling her research program in experimental surface science to international renown. She also pioneered the use of very powerful scanning tunneling microscopes to study the surface of materials like silicon at the atomic level. In 1996, Williams founded the University of Maryland Materials Research Science and Engineering Center, serving as its director until 2009. 

Then industry came knocking. 

“It kind of came out of the blue when I got a phone call from BP,” Williams recalled. “But it was the right phone call. I wanted to become engaged with energy and particularly clean energy topics, and it woke up an old longing in me.”

Williams still remembers the excitement she felt about the first Earth Day. It was 1970, and she was still in high school. 

“It was a time of so many exciting ideas—the women’s movement, anti-war protests,” she said. “And out of all of it, Earth Day really influenced my thinking. Hearing about pollution and the impact on the environment of the wanton wastefulness and carelessness with which resources were being treated deeply offended me and made me feel very eager to have the world protected, and to make it right.”

Williams, who grew up hiking and camping with her family and learned about nature in part through Girl Scouts, said the call from BP reminded her of those earlier stirrings. 

“I realized I still had a deep-seated desire to help make this right,” she said. “And this was an opportunity to do that. I said to myself, ‘I really think it's time for me to just step up and work on this social problem.’” 

Williams took the job as BP’s chief scientist in 2010 after making it clear that one of the things she wanted to do was explore the broad impacts of a variety of energy production technologies on everything from carbon dioxide emissions to land, water and mineral use. Williams’ team at BP was responsible for the review process of all of the company’s applied research activities, which included producing oil and gas as well as developing alternative energy sources. 

 “That was such an amazing learning experience for me to really understand how the energy industry works,” Williams said. “It gave me a lot of confidence to think and speak about the transitions that we're facing and the realities of what's difficult, what's not difficult and what's more important versus what's less important.”  

Her passion and expertise on those subjects attracted the attention of long-time colleague Ernest Moniz. As the U.S. Secretary of Energy under President Obama, Moniz tapped Williams to run ARPA-E, which has a mission to advance high-potential, high-impact energy technologies that are too early in development for private-sector investment. 

“This was a dream job,” Williams remembers, despite a grueling yearlong Senate confirmation process that culminated in her appointment in late 2014. “The administration's policy was to explore ‘all of the above,’ that is all approaches to low-carbon energy production. ARPA-E was founded on the same kind of principles as DARPA, the Defense Advanced Research Projects Agency, which is to go out, look for high-risk, high-impact technologies, and provide support and resources to help them develop. If it doesn't look good, cancel the work quickly and move on. If it does look good, give it a good, hard push and see what you can do.” 

One of Williams’ goals while at ARPA-E was to establish a documentation process for research outcomes, so that every project, whether it succeeded or failed, would have a record of what worked or didn’t and a detailed explanation of why to help guide any future explorations in similar areas. 

The experience of running ARPA-E gave Williams a new appreciation for government work and all the elements that go into successful new technologies beyond the science-based research and development—the financing and business aspects, the market forces and the policy that impacts a new technology’s success or failure.  

In 2017, with a shift in administration, Williams returned to UMD, and it wasn’t long before she was asked to lead ESSIC, which supports research that explores interactions between land, ocean, and atmospheric processes and the influence of the human imprint on our planet. As the largest research center at UMD, ESSIC provides the perfect opportunity for Williams to address issues of climate change in a multidisciplinary, collaborative setting. And she brings plenty of experience working with satellite data at both ARPA-E and as a consultant on nuclear disarmament issues for the U.S. government. 

Williams sees an important role for ESSIC in informing various sectors of society as they adapt to a rapidly changing climate, from helping farmers understand shifts in climate zones and crop tolerances to informing infrastructure planners about water availability. 

“We have amazing Earth system data coming to us from satellites, and the fact that we can make choices about what data we collect makes it possible for us to help people prepare to adapt to and deal with the climate change issues that we can't stop immediately,” Williams said. “If we stop burning so much fossil fuel, we will certainly slow down the process, but the train is moving and some of these changes are still going to happen and have to be reversed later.”  

Bridging the gap between science, technology and policy has become a central focus of Williams’ work. Shortly after returning to UMD, she took the lead on a report mandated by the Maryland legislature that provided in-depth analysis of the state’s support of clean energy and offered recommendations to elevate Maryland’s leadership in clean energy innovation with economic benefits to its citizens. 

Building bridges between sectors was also the subject of a course Williams developed and taught when she returned to UMD in 2017. The course, PHYS 662/PLCY699B: Intersections of Technology and Policy in Modernizing the Energy System, brought together public policy, science and engineering students to develop workable ideas for technologies to mitigate climate change. Although she has taken a break from teaching while she settles in at ESSIC, Williams hopes to offer the course again soon, because building partnerships across sectors and inspiring young researchers to collaborate is important to Williams.  

It was also very important to her late husband, Neil Gehrels, who was a College Park Professor of Astronomy at UMD and chief of the Astroparticle Physics Laboratory at NASA's Goddard Space Flight Center. When Gehrels was awarded the prestigious Dan David Prize shortly before his death from cancer in 2017, Williams donated his share of the prize money to UMD to establish the Neil Gehrels Memorial Endowment in Astrophysics. The endowment provides postdoctoral fellowships to support collaborations between UMD and NASA Goddard scientists.  

Supporting young scientists is something Williams knows about on a personal level as well, having raised a son who is an electrical engineer and a daughter with a Ph.D. in applied physics. Williams described having a household full of scientific minds as “phenomenal” and said it was thrilling to have such a profound sense of intellectual engagement in her home life as well as her professional life.  

On the professional front, Williams said she feels fortunate to have had the opportunity to pursue basic scientific questions in her earlier career and then to address important solutions to societal challenges as she’s doing now.  

“Basic science has played a huge, huge role in our ability to understand what's going on with the Earth and what's likely to happen in the future,” she said. “I think we're in an amazing place right now to be able to apply some of that understanding to real-life issues and to help address what’s happening in a meaningful way.”  

Wherever her career takes her next, Williams will surely be working hard to bring meaningful, intelligent change that makes the world a little better.

Written by Kimbra Cutlip