Real-space visualization of short-range antiferromagnetic correlations in a magnetically enhanced thermoelectric

Abstract

Short-range magnetic correlations can significantly increase the thermopower of magnetic semiconductors, representing a noteworthy development in the decades-long effort to develop high-performance thermoelectric materials. Here, we reveal the nature of the thermopower-enhancing magnetic correlations in the antiferromagnetic semiconductor MnTe. Using magnetic pair distribution function analysis of neutron scattering data, we obtain a detailed, real-space view of robust, nanometer-scale, antiferromagnetic correlations that persist into the paramagnetic phase above the Néel temperature $T_{\mathrm{N}}$ = 307 K. The magnetic correlation length in the paramagnetic state is significantly longer along the crystallographic $c$ axis than within the $ab$ plane, pointing to anisotropic magnetic interactions. Ab initio calculations of the spin-spin correlations using density functional theory in the disordered local moment approach reproduce this result with quantitative accuracy. These findings constitute the first real-space picture of short-range spin correlations in a magnetically enhanced thermoelectric and inform future efforts to optimize thermoelectric performance by magnetic means.

References in corpus (5)

• Mantid - Data Analysis and Visualization Package for Neutron Scattering and $\mu SR$ Experiments
• Magnetic structure determination from the magnetic pair distribution function (mPDF): ground state of MnO
• Temperature-dependent magnetocrystalline anisotropy of rare earth/transition metal permanent magnets from first principles: The light RCo${}_5$ (R=Y, La-Gd) intermetallics
• Onset of Magnetic Order in Strongly-Correlated Systems from ab initio Electronic Structure Calculations: Application to Transition Metal Oxides
• Neutron scattering investigation of proposed Kosterlitz-Thouless transitions in the triangular-lattice Ising antiferromagnet TmMgGaO4

Cited by in corpus (11)

• Sensitivity of the MnTe valence band to orientation of magnetic moments
• Stoichiometry-induced ferromagnetism in altermagnetic candidate MnTe
• DIFFPY.MPDF: Open-source software for magnetic pair distribution function analysis
• A New Spin on Material Properties: Local Magnetic Structure in Functional and Quantum Materials
• Tuning the magnetic properties of the spin-split antiferromagnet MnTe through pressure
• Quantitative investigation of the short-range magnetic correlations in candidate quantum spin liquid NaYbO${}_2$
• Probing Short-Range Correlations in the van der Waals Magnet CrSBr by Small-Angle Neutron Scattering
• Magnetic Pair Distribution Function Data Using Polarized Neutrons and ad hoc Corrections
• Local atomic and magnetic structure of multiferroic (Sr,Ba)(Mn,Ti)O${}_3$
• Symmetry-mode analysis for local structure investigations using pair distribution function data
• Cluster spin glass correlations and dynamics in Zn${}_{0.5}$Mn${}_{0.5}$Te