# Thomas Rosenbaum

Thomas Felix Rosenbaum (born February 20, 1955) is an American condensed matter physicist, professor of physics, and the current president of the California Institute of Technology (Caltech). Previously, Rosenbaum served as a faculty member and Provost of the University of Chicago. He has also served as the vice president for research at Argonne National Laboratory.
As president of Caltech, Rosenbaum has advanced the institution's commitment to scientific research and education through the initiation of numerous innovative programs and institutes. His contributions range from boosting diversity in STEM through fellowships and research funding opportunities, to establishing a number of initiatives through the largest campaigns in Caltech's history.

## Early life and education

Rosenbaum grew up in Queens, New York City, where he spent much of his time playing basketball and frequenting theater and jazz productions. He is of German-Jewish descent, with both sets of his grandparents having left Germany after World War II. During the height of the Cold War, Rosenbaum was inspired by the Apollo program and the Moon landings to pursue physics as a means to solve the world's problems. He attended Forest Hills High School in Queens, and was a finalist in the 1973 Westinghouse Science Talent Search. He received his bachelor's degree in physics with honors from Harvard University in 1977. He then went on to work with Professor Gordon A. Thomas at Princeton University, where he earned his Ph.D. in 1982.

## Career

Rosenbaum conducted research at Bell Laboratories, Murray Hill, New Jersey, and at IBM Thomas J. Watson Research Center, Yorktown Heights, New York, before he joined the University of Chicago faculty in 1983. From January 2007, Rosenbaum served as the provost of the University of Chicago. In addition to his responsibilities for academic and research programs across the University, Rosenbaum served and continues to serve on the board of governors for Argonne National Laboratory. He directed the university's Materials Research Laboratory from 1991 to 1994, the university's James Franck Institute, an interdisciplinary research unit, from 1995 to 2001, and served as vice president for research and for Argonne National Laboratory from 2002 to 2006. He is a member of the board of directors of the Bulletin of the Atomic Scientists and the Santa Fe Institute Science Board, a trustee of the National Opinion Research Center (NORC), and a trustee of the University of Chicago Medical Center. Rosenbaum was announced as the eighth president of The California Institute of Technology on the morning of October 24, 2013 and took office at Caltech on or about July 1, 2014. Rosenbaum was formally inaugurated into the office on October 24, 2014.

## Research

Rosenbaum is an expert on the quantum mechanical nature of materials—the physics of electronic, magnetic, and optical materials at the atomic level—that are best observed at temperatures near absolute zero. Rosenbaum recognized early the significance and ubiquity of quantum phase transitions—from metal–insulator transitions to magnetism to exotic superconductivity—and his work is recognized as putting quantum transitions on as solid a footing as that long available for classical transitions. He has both exploited and advanced methods in experimental low temperature physics, developing new techniques (hydrostatic pressure, stress, magnetometry, calorimetry) for high-resolution studies at milliKelvin temperatures, complementing laboratory dilution refrigerator approaches with synchrotron x-ray measurements in diamond anvil cells at cryogenic temperatures. He established the nature of the metal-insulator transition in doped semiconductors and correlated materials, and demonstrated macroscopic anisotropy of non-s-wave superconductivity in heavy fermion compounds. Rosenbaum’s experiments on magnets involve controllable tuning of quantum fluctuations in both ordered and disordered systems. He is interested in the macroscopic manifestations of quantum mechanics and harnessing disorder to craft a material’s electrical, magnetic, and optical response.

## Initiatives

In Rosenbaum's tenure as president of Caltech, more new initiatives were implemented at the institute than under any previous presidential administration. Under Rosenbaum's leadership, Caltech launched the Resnick Sustainability Institute, the Bioscience Initiative, the Chen Neuroscience Institute, the Rothenberg Innovation Initiative, and the Merkin Translational Institute, among others. More recently, Rosenbaum launched the Hurt Scholars Program and the Initiative for Caltech's Students, reinforcing academic excellence and student development. He also spurred transformational work in seismology at Caltech and advanced research initiatives at the Jet Propulsion Laboratory (JPL).
Alongside his wife, materials scientist Katherine Faber, Rosenbaum has been instrumental in establishing numerous graduate fellowships and research funding opportunities. Among their most notable contributions is the $100,000 graduate research fellowship they initiated at the University of Chicago's Pritzker School of Molecular Engineering in 2014. This fellowship, designed to enhance the representation of women in STEM fields, offers summer research support to graduate students and diversity in the sciences.
Rosenbaum and Faber also established the Guy Rindone Graduate Research Fund which aims to facilitate graduate students' selection of research topics and contributing to the breadth of a student's educational journey. Their philanthropic work continued with their significant contribution to the Gordon and Betty Moore Graduate Fellowship Match at Caltech in 2017. Following this, they initiated the Rosenbaum-Faber Family Graduate Fellowship. This fellowship underscores Rosenbaum's dedication to academic freedom, providing graduate students the flexibility to potentially adjust their research paths based on unforeseen results.

## Personal life

Rosenbaum is married to materials scientist and expert in ceramic engineering and mechanical behavior, Katherine T. Faber. Together, they have two sons, Daniel and Michael. Rosenbaum is of Jewish heritage.

## Honors

His honors include an Alfred P. Sloan Research Fellowship, an NSF Presidential Young Investigator Award, and the William McMillan Award for "outstanding contributions to condensed matter physics". Rosenbaum is an elected Fellow of the American Physical Society, the American Association for the Advancement of Science, and the American Academy of Arts and Sciences.