Mechanical Strain Alters Magnetic Behavior in Emerging Altermagnetic Materials

Researchers at the Department of Energy’s Oak Ridge National Laboratory have demonstrated that applying a small mechanical squeeze can dramatically change the magnetic behavior of altermagnets, an emerging class of magnetic materials. Using neutron scattering techniques, the experimental investigation revealed that mechanical strain directly modifies the internal magnetic structure of these candidate compounds.

The experimental work focused on testing crystals of manganese telluride and iron sulfide. To apply controlled mechanical strain, the research team squeezed these tiny crystal specimens between two titanium plates, examining how physical compression influences their magnetic and electronic states.

To observe the resulting internal changes, the scientists conducted neutron diffraction measurements at Oak Ridge National Laboratory’s Spallation Neutron Source, a Department of Energy Office of Science user facility. The diffraction data demonstrated that uniaxial mechanical strain altered the materials’ magnetic domain populations and shifted an electrical response known as the anomalous Hall effect.

These findings, reported in back-to-back publications in Physical Review X and Advanced Materials, suggest that mechanical strain could offer a straightforward method for controlling magnetism and electron flow in materials under evaluation for spintronic technologies. Spintronics, short for spin electronics, utilizes electron spin in addition to conventional charge to store and process data, contrasting with traditional electronics that relies solely on electron charge.

Researchers note that identifying and controlling suitable foundational materials, including altermagnets, could enable spintronics to advance technologies ranging from wireless communication to quantum computing. “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 co-author Pengcheng Dai of Rice University, a former neutron scientist at Oak Ridge National Laboratory.

The measurements highlighted the capability of neutron scattering to reveal subtle physical mechanisms directly within the strained crystal lattice. “What’s exciting is that one creative experimental idea — a small mechanical squeeze between two plates — can reveal entirely new magnetic behavior and push the field forward, and neutron scattering plays such a critical role, revealing the underlying change in magnetism,” said Feng Ye, an Oak Ridge National Laboratory neutron scientist and co-author on both papers.

The research demonstrates a practical route for tuning the functional properties of emerging altermagnetic systems. Oak Ridge National Laboratory is managed by UT-Battelle for the Department of Energy’s Office of Science, which supports basic research in the physical sciences.

Comparative before and after neutron diffraction patterns recorded during the experimental study illustrate how mechanical compression directly modifies the magnetic domain populations within altermagnetic materials. By positioning tiny crystals of manganese telluride and iron sulfide between two titanium plates, the research team applied physical strain to evaluate how mechanical force alters internal magnetic structures. The resulting diffraction measurements collected at the Spallation Neutron Source confirmed that this mechanical strain shifted the distribution of domain populations while simultaneously altering an electrical transport response identified as the anomalous Hall effect. The experimental observations demonstrate that a straightforward mechanical squeeze between plates provides an effective mechanism for tuning both electron flow and underlying magnetic behavior in candidate altermagnets.

Controlling these domain populations is central to advancing spintronic technologies, which utilize the intrinsic spin of electrons alongside electron charge to store and process data. Conventional electronics depends exclusively on electron charge, making the integration of spin-dependent transport a fundamental shift in technological design. According to the investigators, establishing control over magnetic domains directly governs transport behavior, creating a viable path for deploying emerging altermagnets in advanced applications. If researchers can successfully identify and control the necessary foundational materials, spintronics holds the potential to transform diverse fields ranging from wireless communication networks to quantum computing platforms.

Detailed across linked publications in Physical Review X and Advanced Materials, the peer-reviewed findings highlight how critical neutron scattering is for revealing subtle changes in magnetism that might otherwise remain hidden. Squeezing crystal specimens between plates pushed the research field forward by confirming that simple uniaxial strain directly governs the physical behavior of candidate altermagnets. The experimental work relied on the Spallation Neutron Source, a Department of Energy Office of Science user facility operated at Oak Ridge National Laboratory under UT-Battelle management.

Subject of Research: Mechanical strain control of magnetic behavior in altermagnets

Article Title: Simple squeeze changes magnetic behavior in emerging materials

Article References: Simple squeeze changes magnetic behavior in emerging materials. Original publication (Bibliographic details unavailable.)

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Keywords: altermagnets, spintronics, neutron diffraction, Oak Ridge National Laboratory, condensed matter physics, magnetic domains, anomalous Hall effect, materials science, Simple, squeeze, changes, magnetic