Xi Wang, assistant professor of physics at Washington University in St. Louis, has received a highly competitive U.S. Department of Energy (DOE) Early Career Research Program award to pursue fundamental research at the frontier of opto-spintronics, an emerging field that seeks to use light to control magnetic states in quantum materials.
Xi Wang is among just 67 early-career scientists from universities and DOE national laboratories nationwide selected for the 2026 program. The DOE announced $96 million in total funding for this year’s awardees on Oct. 8. Widely regarded as one of the DOE’s most prestigious honors for early-career researchers, the program supports outstanding scientists pursuing ambitious, high-impact fundamental research that can shape the future of their fields.
Wang’s project, “Exciton-Spin Coupling for Optical Control of Spin States in Low-Symmetry vdW Heterostructures,” will explore a fundamental question in quantum materials: Can light be used to selectively, efficiently and reversibly control magnetism at the atomic scale?
The research focuses on atomically thin, two-dimensional magnetic semiconductors, in which optical, magnetic and structural properties are intimately intertwined. This unusual coupling creates opportunities not only to uncover new fundamental physics, but also to establish entirely new approaches for manipulating magnetic information. Ultimately, such capabilities could contribute to faster and more energy-efficient technologies for information processing, sensing and communication.
At the heart of the project are excitons — bound pairs of electrons and positively charged holes created when a material absorbs light. Wang’s group will investigate how these light-generated excitations interact with magnetic order and whether they can be harnessed as a precise tool for controlling spin states.
To create and manipulate these states, Wang’s team will twist atomically thin materials relative to one another and engineer the interfaces between them, producing quantum systems in which multiple magnetic states compete. They will then test whether light can selectively drive the material from one magnetic state to another and switch it back again.
The work brings together strain tuning, moiré and interfacial engineering, magneto-optical spectroscopy, and nanoscale magnetic and structural characterization. These complementary approaches will allow Wang’s group to reveal how reduced symmetry, atomic-scale structural reconstruction and interactions between neighboring layers determine the magnetic landscape of these materials.
By connecting atomic-scale structure to optical excitation and magnetic behavior, Wang and her team aim to establish a predictive framework for designing quantum materials whose spin states can be controlled on demand with light.
Such a framework could open a new direction for spintronics and optoelectronics, where magnetic states are manipulated without direct electrical contact and potentially with greater speed and lower energy consumption. More broadly, the project could uncover fundamental principles governing the interaction of light, spin and magnetism in low-dimensional quantum materials.
The DOE Early Career Research Program award will provide five years of support for Wang’s group to pursue these fundamental questions and advance the high-impact science the program is designed to foster.
