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Ytterbium manganese dibismuthide, or YbMnBi₂, is a magnetic compound that Rice University physicist Pengcheng Dai and his team found can enter an unusual state: a magnetic liquid crystal. In a recent study published in Physical Review X, the researchers heated YbMnBi₂ until its normal magnetic order disappeared. Surprisingly, its magnetic spins did not become completely random. Even while fluctuating, they still preferred certain directions.

“In a conventional magnet, once you heat above the magnetic ordering temperature, you expect the spins to lose their directional organization,” said Dai, the Sam and Helen Worden Professor of Physics and Astronomy. “What we find in YbMnBi₂ is different. The magnetic order disappears, but the fluctuating spins still prefer certain directions. In this sense, the system behaves like a magnetic liquid crystal.”

Researchers at the Department of Energy’s (DOE) Oak Ridge National Laboratory (ORNL) used neutrons to reveal how a small mechanical squeeze can dramatically change the magnetic behavior of an emerging class of magnetic materials known as altermagnets.

“By controlling the magnetic domains, we can directly influence the transport behavior, and that opens the door to exploring these materials for spintronic technologies,” said Pengcheng Dai of Rice University, a former neutron scientist at ORNL.

Phys.org has featured our recent Physical Review X study of YbMnBi₂. Using polarized neutron scattering, we found that magnetic fluctuations develop a preferred direction above the temperature where long-range magnetic order appears, forming a dynamic spin nematic state analogous to a liquid crystal. Our results offer a possible explanation for the material’s unusual Hall and Nernst responses and suggest a route to controlling electronic behavior through collective spin correlations.

Read the paper: Phys. Rev. X 16, 041001 (2026).

Rice researchers and collaborators demonstrated that uniaxial strain can tune the anomalous Hall effect in the altermagnet manganese telluride (MnTe), including reversing its sign. Published in Physical Review X, the study also showed that strain selects a single magnetic domain, allowing the team to resolve the magnetic structure and sharpen the Hall response. The sign reversal occurs without shifting the magnetic transition temperature, pointing to strain-induced changes in electronic Berry curvature and offering a route to mechanical control of altermagnetic transport.

Read the paper: Phys. Rev. X 16, 031033 (2026).

A gentle squeeze has helped Rice physicists uncover a close link between weak magnetism and the anomalous Hall effect in hexagonal iron sulfide (h-FeS). Reporting in Advanced Materials, the team showed that compressive strain suppresses the tiny net magnetic moment and the Hall signal together. Neutron diffraction revealed changes in magnetic domain populations, while the underlying in-plane magnetic structure remained intact. The findings show how strain can control these coupled properties in an altermagnet candidate.

Read the paper: Adv. Mater. e74398 (2026).

"Leading researchers from around the world gathered in Paris June 9-12 for the 2026 Rice Center for Quantum Materials and Korean Academy of Science and Technology InterAcademy Global Workshop on Quantum Materials Synthesis, a four-day meeting focused on advancing one of the most important frontiers in modern materials research."

''Rice University professor Pengcheng Dai has been elected to the American Academy of Arts and Sciences, one of the oldest and most prestigious learned societies in the nation.

Professor Dai’s election to the American Academy of Arts and Sciences recognizes the profound impact of his work in condensed matter physics,” said Amy Dittmar, the Howard R. Hughes Provost and executive vice president for academic affairs. “His contributions are advancing understanding in his field and exemplify the kind of rigorous, high-impact scholarship that defines Rice. This honor highlights both his leadership as a researcher and the global reach of our faculty’s work.

Dai is being recognized for establishing spin excitations as the unifying experimental signature linking magnetism and superconductivity across unconventional superconductors. His neutron scattering experiments provided decisive evidence connecting magnetic correlations to superconducting pairing in both cuprates and iron-based superconductors."

"Magnetic materials in a quantum spin liquid phase are of great interest in the pursuit of exotic state of matter and quantum computation. But in the quantum realm, things are not always what they seem. A recent study, published in Science Advances and co-led by Rice University’s Pengcheng Dai, found that the material cerium magnesium hexalluminate (CeMgAl11O19) was not actually in a quantum spin liquid phase despite evidence suggesting it was."

"Quantum materials underpin next-generation technologies, from quantum computing to ultra-efficient electronics. To accelerate discovery in these emerging fields, Rice University hosted the 2025 Rice Center for Quantum Materials (RCQM) Winter School on Quantum Materials Synthesis and Workshop on Quantum Geometry Nov. 10-14, bringing together more than 100 researchers, students and scientific leaders from around the world."

"More than 80 scientists from around the world gathered at Rice University for the eQMA Workshop on Hidden Orders and Quantum Entanglement, part of the UNESCO 2025 International Year of Quantum Science and Technology celebration. Hosted by the Extreme Quantum Materials Alliance (eQMA) in collaboration with Rice’s Smalley-Curl Institute, the three-day event Oct. 6-8 featured lectures, discussions and collaborative exchanges among leading theorists and experimentalists in the field."

"Four physicists from Rice University have received a $4.4 million grant over three years from the U.S. Department of Energy to establish the Rice Laboratory for Emergent Magnetic Materials (RLEMM). This new research center will investigate the fundamental interactions of magnetism and its role in next-generation technologies."

"An international team of scientists led by Rice University’s Pengcheng Dai has confirmed the existence of emergent photons and fractionalized spin excitations in a rare quantum spin liquid. Published in Nature Physics on June 19, their findings identify the crystalline compound cerium zirconium oxide (Ce₂Zr₂O₇) as a clear, 3D realization of this exotic state of matter."

"Led by Pengcheng Dai, the Sam and Helen Worden Professor of Physics and Astronomy, the researchers uncovered the cause behind a vanishing electronic phenomenon in a class of crystalline materials known as kagome lattice, a geometric arrangement of corner-sharing triangles named after a traditional Japanese basket pattern. This discovery reveals how heating methods impact the presence of a charge density wave (CDW), a quantum pattern of electron arrangement, in the kagome metal iron germanide (FeGe). It also demonstrates how its reappearance enhances magnetic and electronic properties."

"Organized by Rice University’s Extreme Quantum Materials Alliance (eQMA) in collaboration with the Smalley-Curl Institute, the eQMA Workshop on Quantum Materials and Entanglement brought together more than 100 experts and attendees from across the globe to discuss cutting-edge advancements in quantum research.

Rice students played an active role in the discussions. Bin Gao, a postdoctoral associate in physics and astronomy, presented on the emergent photons and fractionalized excitations in a quantum spin liquid......"

"The Rice Center for Quantum Materials at Rice University recently hosted the second edition of the Workshop on Quantum Materials Synthesis, an event dedicated to communicating recent developments in the field, identifying new research areas and providing a platform for theorists and experimentalists to come together for discussion and knowledge exchange."

Physicists in the US have discovered a material that could qualify as the first known three-dimensional example of a quantum spin liquid - an exotic theoretical phase of matter.