Magnetic structure of EuCd$_2$Sb$_2$ single-crystal thin-film
Abstract: We investigate the magnetic order in single crystalline EuCd$_2$Sb$_2$ thin films using a combined theoretical and experimental approach. Resonant elastic x-ray scattering experiments reveal a sharp magnetic peak at $q = (0, 0, \frac{1}{2})$ below $T_N = 7.2$ K, indicative of interlayer antiferromagnetic ordering. Additionally, we observe a weak diffuse magnetic signal centered at $q = (0, 0, 1)$ that persists above $T_N$, up to $T_C \sim 11$ K. Our Monte-Carlo simulations of a classical spin model approximation of the Eu magnetic sublattice demonstrate that the diffuse signal can arise from ferromagnetic coupling in the top few layers due to surface oxidation. On the other hand, the bulk of the sample exhibits antiferromagnetic coupling between layers. Finally, our fit of the model parameters to the magnetic ordering temperatures, shed light on the exchange couplings that are key in stabilizing the observed composite magnetic order.
- H. Weyl, Elektron und gravitation. I, Zeitschrift für Physik 56, 330 (1929).
- B. A. Bernevig, C. Felser, and H. Beidenkopf, Progress and prospects in magnetic topological materials, Nature 603, 41 (2022).
- Y. Tokura, K. Yasuda, and A. Tsukazaki, Magnetic topological insulators, Nature Reviews Physics 1, 126 (2019).
- N. Armitage, E. Mele, and A. Vishwanath, Weyl and Dirac semimetals in three-dimensional solids, Reviews of Modern Physics 90, 015001 (2018).
- B. Q. Lv, T. Qian, and H. Ding, Experimental perspective on three-dimensional topological semimetals, Rev. Mod. Phys. 93, 025002 (2021).
- E. Weschke and E. Schierle, The UE46 PGM-1 beamline at BESSY II, Journal of large-scale research facilities JLSRF 4, A127 (2018).
- J. P. Hill and D. F. McMorrow, Resonant Exchange Scattering: Polarization Dependence and Correlation Function, Acta Crystallographica Section A 52, 236 (1996).
- E. Heinrich, T. Posske, and B. Flebus, Topological magnetic phase transition in eu-based a-type antiferromagnets, Physical Review B 106, 10.1103/physrevb.106.214402 (2022).
- U. Wolff, Collective monte carlo updating for spin systems, Phys. Rev. Lett. 62, 361 (1989).
- S. Kirkpatrick, C. D. Gelatt, and M. P. Vecchi, Optimization by simulated annealing, Science 220, 671 (1983).
- J. Kent-Dobias and J. P. Sethna, Cluster representations and the wolff algorithm in arbitrary external fields, Phys. Rev. E 98, 063306 (2018).
- Manipulating magnetism in the topological semimetal EuCd2As2, Phys. Rev. B 101, 140402 (2020).
- B. Flebus, Magnetoresistance driven by the magnetic berezinskii-kosterlitz-thouless transition, Phys. Rev. B 104, L020408 (2021).
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