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O: Fachverband Oberflächenphysik

O 11: Electronic Structure of Surfaces: Spectroscopy, Surface States I

O 11.6: Vortrag

Montag, 17. März 2025, 16:15–16:30, H4

Electronic structure of ferromagnetic CrTe — •Chien-Wen Chuang¹, Muthu P.T. Masilamani¹, Hibiki Orio¹, Maximilian Ünzelmann¹, Chia-Nung Kuo^2,3, Chin-Shan Lue^2,3, Ashish Chainani⁴, and Friedrich Reinert¹ — ¹Exp. Physik VII and Würzburg-Dresden Cluster of Excellence ct.qmat, Universität Würzburg, Würzburg, Germany — ²Department of Physics, National Cheng Kung University, Tainan, Taiwan — ³Taiwan Consortium of Emergent Crystalline Materials, National Science and Technology Council, Taipei, Taiwan — ⁴National Synchrotron Radiation Research Center, Hsinchu, Taiwan

Recent studies showed that CrTe and doped CrTe exhibit various emergent properties, such as a large magnetocaloric effect, spontaneous skyrmions and ferromagnetism with high Curie temperature T_C∼340 K. We carried out Cr L-edge (2p-3d) X-ray absorption spectroscopy (XAS) and resonant photoemission spectroscopy (Res-PES) with right and left circularly polarized light on single crystal CrTe to investigate the role of Coulomb correlations in Cr 3d density of states(DOS). The Res-PES spectra showed a resonantly enhanced sharp peak at a binding energy of 1.5 eV, which corresponds to the Cr main 3d DOS, while states at the Fermi level do not show a clear resonance enhancement. A small circular dichroism of Cr 3d DOS was observed. In addition, we observed the Cr 3d two-hole L₃VV Auger feature which corresponds to a correlation satellite. Using the Cini-Sawatzky method, we estimate the on-site Coulomb interaction energy in Cr 3d states to be U_dd∼3 eV.

Keywords: Ferromagnetism; XAS; Res-PES