For as long as he could remember, Brenden Ortiz wanted to do only one thing.
“My childhood dream was to be a scientist. All I wanted to do was tinker in a lab like a pure scientist,” Ortiz said.
Now a Eugene P. Wigner Distinguished Staff Fellow at the Department of Energy’s Oak Ridge National Laboratory, his dream has come true. Ortiz is a scientist in the Correlated Electron Materials Group of the Materials Science and Technology Division, studying ways to control and predict electronic instabilities in correlated metals, whose electrons interact in coordinated yet complex ways.
“Understanding the connection between the electronic structure of materials and the emergence of correlated electron properties will allow us to design the next generation of quantum materials,” Ortiz said, adding that the work provides material platforms for the exploration of fundamental materials physics.
Ortiz, who discovered a new family of metals while he was a doctoral student and then a postdoctoral researcher, now focuses his research on designing quantum materials under ORNL mentors Michael McGuire and Andrew May. However, his research first caused a stir before his 2023 arrival at ORNL.
During his doctoral work at the Colorado School of Mines, Ortiz worked on discovering and engineering new thermoelectric materials, which can generate electricity directly from heat. While exploring semiconductors known as Zintls, Ortiz discovered a new class of metals with unusual properties. The metals had a distinct structure called a kagome lattice, superconductor properties and a charge density wave — a trio of properties that had never been seen together before. He brought this research with him to the University of California, Santa Barbara, where he would develop the materials toward quantum applications during a postdoctoral fellowship.
“Because this is the only material in the world so far that has these three properties, it provides an opportunity to study how these different states interact with each other,” Ortiz said. “It provides a platform to do research. The material allows theorists to test their theories, and on the application side, industry may be able to build on it.”
Once Ortiz had developed a method to grow these metallic crystals, the request for samples starting rolling in.
“People went ‘insane,’” Ortiz said. “From the moment we published a paper showing the new metal had a superconducting ground state, all we did was respond to people needing the crystals. In just over two years, more than 400 new citations and 350 manuscripts on this family of metals have been published, and we struck collaborations with researchers around the world.”
Superconductivity is the ability of a material to conduct electricity without resistance — a highly valued property in science and industry. An electric current through a loop of superconductor can last practically indefinitely and enables the generation of strong magnetic fields. As Ortiz’s material cools, electrons in the metal begin to interact and form a standing wave – called a charge density wave. The coexistence of the charge density wave and superconductivity is a rare occurrence, and Ortiz’s material is the first example of these phenomenon existing together on a kagome motif. Named for a pattern seen in Japanese basket weaving, the kagome motif appears in some minerals and is prized for its unusual physical properties. The geometry of triangles and hexagons that leads to the kagome motif often imparts some unusual properties. For example, some researchers believe the charge density wave may even carry small loops of electric current, leading to some exotic electronic and magnetic properties.
The discovery paved the way for a research focus at ORNL, where, Ortiz said, he has a trove of resources and experts to try out his ideas.
That dedication to science led Ortiz from a childhood dream to a national energy laboratory. Originally from Pueblo, Colorado, he grew up the oldest of three children whose American roots go back many generations — too many to know for certain because he has Native American ancestry. His father was a researcher for the U.S. Department of the Interior in water resources, and his mother taught elementary school science and math. He loved video games. He also read. A lot.
“As a kid, there was one book I continually checked out of the library. It was on radioactivity and nuclear energy. The librarian would say, ‘You can’t read that,’ but I kept reading it and I loved it,” Ortiz recalled. Now, he enjoys hearing colleagues talk about those subjects.
His love of reading also brought him to new worlds. Science fiction, especially space adventures, captivated Ortiz as a child, and he would imagine what it would be like to have exotic elements like those the authors dreamed up. Now he is discovering unique materials that can influence science and society.
Always fascinated by rocks and minerals in Colorado, Ortiz was awed “by the sheer variety of materials lying underneath our feet. When I was exposed to metallurgy and materials science as an undergraduate, I saw a route to marry chemistry, physics and geology all at once. Nature still provides the inspiration for many of my crystal growth experiments.”
His parents encouraged him to try different things to see what he liked. In fact, “I was required to try everything once,” he said. With his father’s encouragement, he tried every sport available, and one of them stayed with him: he still plays ice hockey weekly in Knoxville, Tennessee, with colleagues from ORNL’s High Flux Isotope Reactor, a DOE Office of Science user facility.
An interest in food science led Ortiz to become a certified nutrition coach. In his spare time, he is creating a nutritious but low-calorie protein bar. However, physical activity is at the top of his list to keep his body and mind sharp. His mother, an aerobics instructor and bodybuilder, also encouraged an active lifestyle. Ortiz came to Knoxville shortly after competing in a bodybuilding show himself, and though rock climbing was a favorite Colorado pastime, he has not found time yet for the Tennessee rocks.
What brought him to this fellowship is what will keep him enjoying the work. “I don’t want to just sit at a desk; I want to do science with my own hands,” Ortiz said. “To have the opportunity to have a presence in the lab and collaborate with a network of national labs across the country is great. And, of course, the facilities are top notch.”
The potential to harness material properties for new technological advances is also a big reason to do research at a national laboratory. “Growing high-quality crystals, doing characterizations ourselves — these are important,” Ortiz said. “The group is a tight ship with good scientists. Everyone has a specialty, and they are very much about teamwork, which is something I needed. It’s a collaboration with peers.”
ORNL’s Distinguished Staff Fellowship program aims to cultivate future scientific leaders by providing dedicated mentors, world-leading scientific resources and enriching research opportunities. Fellowships are awarded to outstanding early-career scientists and engineers who demonstrate success within their academic, professional and technical areas. Fellowships are awarded for fundamental, experimental and computational sciences in a wide range of science areas.
UT-Battelle manages ORNL for DOE’s Office of Science, the single largest supporter of basic research in the physical sciences in the United States. DOE’s Office of Science is working to address some of the most pressing challenges of our time. For more information, visit energy.gov/science. — Lawrence Bernard