Experiments in manganese telluride detected magnetic excitations that respond differently to opposite handedness of X-ray light. The result supports altermagnetism, an ordering of spins that can have no overall magnetization. A new announcement marks peer-reviewed publication; the accessible author preprint appeared earlier and leaves some aspects of the signal unresolved.
Manganese telluride has shown a directional magnetic response consistent with altermagnetism, a spin ordering that can persist without overall magnetization. A team led by the US SLAC National Accelerator Laboratory announced the findings upon publication in Science. The signal concerns magnons, collective motions of electron spins within the crystal, rather than the magnetic pull familiar from a permanent magnet.[1], [2]
Experiments took place at the European Synchrotron Radiation Facility, an X-ray research centre in France. Scattering measurements compared the crystal’s response to light with opposite rotational handedness. The difference supplied evidence of handed magnetic excitations, while its variation with momentum agreed with the expected crystal symmetry. This extends the evidence for altermagnetic order from electronic structure into collective spin motion.[1]
An author preprint was already public before the new journal announcement. It discusses a remaining ambiguity when the results are compared with earlier neutron measurements: in some directions, differences in excitation lifetime may contribute more than a resolved separation in energy. More precise measurements could separate those explanations. Interest in spin-based computing remains a prospective application; no working memory or processor emerged from the experiment.[1]
