STROBE in the News

The School of Physical Sciences now has two new Associate Deans. Franklin Dollar of the UCI Department of Physics & Astronomy is the new Associate Dean of Graduate Studies, and Mu-Chun Chen, also of Physics & Astronomy is the new Associate Dean of Diversity, Equity and Inclusion (DEI). Both appointees come from long histories of experience with both engaging with the graduate student community at Physical Sciences, as well as stimulating action in the DEI realm.

Very recently, Dollar was part of an effort in his department to secure funding for the mentors of a graduate student-led program called Physics & Astronomy Community Excellence (PACE), which aims to give graduate students the peer support they may need. “Our vision is to foster a student-focused, transdisciplinary graduate experience in which a diverse student body can both succeed and lead in their chosen path,” Dollar said. “We will develop new support mechanisms to promote broader collaboration across the school, while making sure that students have the support they need.”

A team of physicists at CU Boulder has solved the mystery behind a perplexing phenomenon in the nano realm: why some ultra-small heat sources cool down faster if you pack them closer together. The findings, which will publish this week in the journal Proceedings of the National Academy of Sciences (PNAS), could one day help the tech industry design speedier electronic devices that overheat less.

“Often heat is a challenging consideration in designing electronics. You build a device then discover that it’s heating up faster than desired,” said study co-author Joshua Knobloch, postdoctoral research associate at JILA, a joint research institute between CU Boulder and the National Institute of Standards and Technology (NIST). “Our goal is to understand the fundamental physics involved so we can engineer future devices to efficiently manage the flow of heat.”

For laser science, one major goal is to achieve full control over the spatial, temporal and polarization properties of light, and to learn how to precisely manipulate these properties.  A  property of light is called the Orbital Angular Momentum (OAM), that depends on the spatial distribution of the phase (or crests) of a donut-shaped light beam. More recently, a new variant of OAM was discovered – called the spatial-temporal OAM (ST-OAM), with much more elusive properties, since the phase/crests of light evolve both temporally and spatially. In a collaboration led by senior scientist Dr. Chen-Ting Liao, working with graduate student Guan Gui and JILA Fellows Margaret Murnane and Henry Kapteyn, the team explored how such beams change after propagating through nonlinear crystals that can change their color…

Welcome to the inaugural episode of the President’s Innovation Podcast, a special CU on the Air series. Host Emily Davies speaks with distinguished professor Margaret Murnane, a fellow at JILA, which is a joint institute of the University of Colorado Boulder and the National Institute of Standards and Technology. Dr. Murnane is also a faculty member in the department of physics and electrical and computer engineering at CU Boulder, and has earned numerous prestigious awards for her work in ultrafast laser and x-ray science.

Glass, rubber and plastics all belong to a class of matter called amorphous solids. In spite of how common they are in our everyday lives, amorphous solids have long posed a challenge to scientists.

Since the 1910s, scientists have been able to map in 3D the atomic structures of crystals, the other major class of solids, which has led to myriad advances in physics, chemistry, biology, materials science, geology, nanoscience, drug discovery and more. But because amorphous solids aren’t assembled in rigid, repetitive atomic structures, as crystals are, they have defied researchers’ ability to determine their atomic structure with the same level of precision.

Until now, that is.

UCLA-led research published in the journal Nature reports on the first-ever determination of the 3D atomic structure of an amorphous solid — in this case, a material called metallic glass…

UCLA-led study captures the structure of metallic glass. Glass, rubber and plastics all belong to a class of matter called amorphous solids. And in spite of how common they are in our everyday lives, amorphous solids have long posed a challenge to scientists. Since the 1910s, scientists have been able to map in 3D the atomic structures of crystals, the other major class of solids, which has led to myriad advances in physics, chemistry, biology, materials science, geology, nanoscience, drug discovery and more. But because amorphous solids aren’t assembled in rigid, repetitive atomic structures like crystals are, they have defied researchers’ ability to determine their atomic structure with the same level of precision. Until now, that is. A UCLA-led study in the journal Nature reports on the first-ever determination of the 3D atomic structure of an amorphous solid — in this case, a material called metallic glass.

The positions of all the atoms in a sample of a metallic glass have been measured experimentally — fulfilling a decades-old dream for glass scientists, and raising the prospect of fresh insight into the structures of disordered solids. If the chemical element and 3D location of every atom in a material are known, then the material’s physical properties can, in principle at least, be predicted using the laws of physics. The atomic positions of crystals have long-range periodicity, which has enabled the development of powerful methods that combine diffraction experiments with the mathematics of symmetry to determine the precise atomic structure of these materials. Moreover, deviations from periodicity that create defects in crystals can be imaged with sub-ångström resolution. But these methods do not work for glasses, which lack long-range periodicity. Our knowledge of the atomic structure of glasses is therefore limited and acquired indirectly. Writing in Nature, Yang et al.¹ report the experimental determination of the 3D positions of all the atoms in a nanometre-scale sample of a metallic glass.

Heavy elements and a really powerful microscope help scientists map uncharted paths toward new materials and cancer therapies. Heavy elements known as the actinides are important materials for medicine, energy, and national defense. But even though the first actinides were discovered by scientists at Berkeley Lab more than 50 years ago, we still don’t know much about their chemical properties because only small amounts of these highly radioactive elements (or isotopes) are produced every year; they’re expensive; and their radioactivity makes them challenging to handle and store safely.

The first episode of the inaugural season of Buff Innovator Insights, a new podcast from the Research & Innovation Office (RIO), will premiere on Thursday, March 18. The podcast will offer a behind-the-curtain look at some of the most ground-breaking innovations in the world—all emanating from the CU Boulder campus—along with the personal journeys that made those discoveries possible. Terri Fiez, Vice Chancellor for Research & Innovation, hosts this up-close and personal look at how researchers, scholars and artists become global pioneers, why they are so dedicated to discovery, and their visions of the future in the wide range of fields they explore.

Airing Thursday, March 18: Margaret Murnane–JILA; Physics; STROBE Science & Technology Center

In the first episode of Buff Innovator Insights, we meet Dr. Margaret Murnane, CU Boulder professor of physics and one of the world’s leading experts in ultrafast laser and x-ray science. Join us to learn about her improbable journey from growing up in the Irish countryside to developing the microscopes of the future and cultivating the world’s next generation of physicists.

STROBE is one of the 12 nationwide NSF funded Science and Technology centers. According to Ellen Keister, the STROBE Director of Education: “STROBE research groups have common challenges associated with big data, detectors, as well as pushing the limits of x-ray, electron and visible nano-imaging. STROBE enables research groups to address common challenges, enhance tabletop and national facilities and use new capabilities to address current nano and bio materials challenges.”

While STROBE works on collaboration between investigators within its center, it also encourages collaboration from a younger generation. “STROBE encompasses K-12 outreach, undergraduate education, graduate education programming, essentially focusing on how to build and maintain a top STEM workforce,” Keister comments. “- and do it in a way that is inclusive, and that provides students and trainees with the technical and soft skills and tools they need to be prepared and successful when they go out into the 21st century workforce.”