Explore the vast range of titles available.

Altermagnetism represents an emergent collinear magnetic phase with compensated order and an unconventional alternating even-parity wave spin order in the non-relativistic band structure. We investigate directly this unconventional band splitting near the Fermi energy through spin-integrated soft X-ray angular resolved photoemission spectroscopy. The experimentally obtained angle-dependent photoemission intensity, acquired from epitaxial thin films of the predicted altermagnet CrSb, demonstrates robust agreement with the corresponding band structure calculations. In particular, we observe the distinctive splitting of an electronic band on a low-symmetry path in the Brilliouin zone that connects two points featuring symmetry-induced degeneracy. The measured large magnitude of the spin splitting of approximately 0.6 eV and the position of the band just below the Fermi energy underscores the significance of altermagnets for spintronics based on robust broken time reversal symmetry responses arising from exchange energy scales, akin to ferromagnets, while remaining insensitive to external magnetic fields and possessing THz dynamics, akin to antiferromagnets. The fundamental hallmark of altermagnetism lies in the spin splitting of electronic valence bands. Here, the authors observe splitting in metallic CrSb, revealing an exceptionally large value and energetic placement just below the Fermi energy.

Phases with spontaneous time-reversal ( T ) symmetry breaking are sought after for their anomalous physical properties, low-dissipation electronic and spin responses, and information-technology applications. Recently predicted altermagnetic phase features an unconventional and attractive combination of a strong T -symmetry breaking in the electronic structure and a zero or only weak-relativistic magnetization. In this work, we experimentally observe the anomalous Hall effect, a prominent representative of the T -symmetry breaking responses, in the absence of an external magnetic field in epitaxial thin-film Mn 5 Si 3 with a vanishingly small net magnetic moment. By symmetry analysis and first-principles calculations we demonstrate that the unconventional d-wave altermagnetic phase is consistent with the experimental structural and magnetic characterization of the Mn 5 Si 3 epilayers, and that the theoretical anomalous Hall conductivity generated by the phase is sizable, in agreement with experiment. An analogy with unconventional d-wave superconductivity suggests that our identification of a candidate of unconventional d-wave altermagnetism points towards a new chapter of research and applications of magnetic phases. The classification of magnets now includes altermagnets which possess opposite-spin sublattices connected by rotation and share some features with ferro- and antiferromagnets. Here the authors report the anomalous Hall effect in Mn5Si3 and interpret the results in terms of a d-wave altermagnetic phase.

The anomalous Nernst effect generates a voltage transverse to an applied thermal gradient in some magnetically ordered systems. While the effect was considered excluded in compensated magnetic materials with collinear ordering, in the recently identified symmetry-class of altermagnets, the anomalous Nernst effect is possible despite the compensated collinear spin arrangement. In this work, we show that epitaxial Mn 5 Si 3 thin films grown on Si manifest an anomalous Nernst effect with a finite spontaneous signal at zero magnetic field despite the vanishing spontaneous magnetization. We attribute this to the previously theoretically predicted and experimentally corroborated altermagnetism of epitaxial Mn 5 Si 3 thin films grown on Si. The observed spontaneous anomalous Nernst coefficient reaches the value of 0.26 μV/K with the corresponding spontaneous Nernst conductivity of 0.22 A/(K  ⋅  m). To complement our measurements, we perform density-functional theory calculations of the momentum-resolved anomalous Nernst conductivity, highlighting the contributions of altermagnetic pseudonodal surfaces and ladder transitions to the Berry curvature. Our results illustrate the value of unconventional d-wave wave altermagnets composed of abundant and non-toxic light elements for thermo-electrics and spin-caloritronics. Altermagnets, unlike their conventional collinear antiferromagnetic counterparts, allow for an anomalous Nernst response despite their collinear compensated magnetic ordering. Here, Badura et al find such an anomalous Nernst effect at zero magnetic field in the altermagnetic candidate, Mn 5 Si 3 .

The anomalous Nernst effect generates a voltage transverse to an applied thermal gradient in some magnetically ordered systems. While the effect was considered excluded in compensated magnetic materials with collinear ordering, in the recently identified symmetry-class of altermagnets, the anomalous Nernst effect is possible despite the compensated collinear spin arrangement. In this work, we show that epitaxial Mn Si thin films grown on Si manifest an anomalous Nernst effect with a finite spontaneous signal at zero magnetic field despite the vanishing spontaneous magnetization. We attribute this to the previously theoretically predicted and experimentally corroborated altermagnetism of epitaxial Mn Si thin films grown on Si. The observed spontaneous anomalous Nernst coefficient reaches the value of 0.26 μV/K with the corresponding spontaneous Nernst conductivity of 0.22 A/(K  ⋅  m). To complement our measurements, we perform density-functional theory calculations of the momentum-resolved anomalous Nernst conductivity, highlighting the contributions of altermagnetic pseudonodal surfaces and ladder transitions to the Berry curvature. Our results illustrate the value of unconventional d-wave wave altermagnets composed of abundant and non-toxic light elements for thermo-electrics and spin-caloritronics.

Phases with spontaneous time-reversal ( ) symmetry breaking are sought after for their anomalous physical properties, low-dissipation electronic and spin responses, and information-technology applications. Recently predicted altermagnetic phase features an unconventional and attractive combination of a strong -symmetry breaking in the electronic structure and a zero or only weak-relativistic magnetization. In this work, we experimentally observe the anomalous Hall effect, a prominent representative of the -symmetry breaking responses, in the absence of an external magnetic field in epitaxial thin-film Mn Si with a vanishingly small net magnetic moment. By symmetry analysis and first-principles calculations we demonstrate that the unconventional d-wave altermagnetic phase is consistent with the experimental structural and magnetic characterization of the Mn Si epilayers, and that the theoretical anomalous Hall conductivity generated by the phase is sizable, in agreement with experiment. An analogy with unconventional d-wave superconductivity suggests that our identification of a candidate of unconventional d-wave altermagnetism points towards a new chapter of research and applications of magnetic phases.

The anomalous Nernst effect generates transverse voltage to the applied thermal gradient in magnetically ordered systems. The effect was previously considered excluded in compensated magnetic materials with collinear ordering. However, in the recently identified class of compensated magnetic materials, dubbed altermagnets, time-reversal symmetry breaking in the electronic band structure makes the presence of the anomalous Nernst effect possible despite the collinear spin arrangement. In this work, we investigate epitaxial Mn5Si3 thin films known to be an altermagnetic candidate. We show that the material manifests a sizable anomalous Nernst coefficient despite the small net magnetization of the films. The measured magnitudes of the anomalous Nernst coefficient reach a scale of microVolts per Kelvin. We support our magneto-thermoelectric measurements by density-functional theory calculations of the material's spin-split electronic structure, which allows for the finite Berry curvature in the reciprocal space. Furthermore, we present our calculations of the intrinsic Berry-curvature Nernst conductivity, which agree with our experimental observations.