[행사/세미나] [Seminar] Dec. 29(Thur.) Topological magnetic phases in a magnetically frustrated Kondo-lattice CePtAl4Ge2
- 물리학과
- 조회수3481
- 2022-12-28
양자물질초전도연구실에서 스위스 Paul Scherrer Institute (PSI) 신수현 박사님을 초청하여 아래와 같이 세미나를 개최합니다.
학과 구성원 여러분의 많은 참여를 부탁 드립니다.
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○ Topic: Topological magnetic phases in a magnetically frustrated Kondo-lattice CePtAl4Ge2
○ Speaker: Dr. Soohyeon Shin (스위스 Paul Scherrer Institute (PSI))
○ Date/time: 2022. 12. 29. (Thur.) 11:00 AM
○ Place: General Studies(51), Room No. 51306
○ Abstract: CePtAl4Ge2, in which magnetic Ce atoms form a quasi-two-dimensional triangular lattice, exhibits an antiferromagnetic state below 2.3 K and the amplitude of ordered moments modulates with an ordering wave vector k = (1.39, 0, 0.09) [1]. Single-crystal neutron diffraction experiments have been recently performed and revealed that the zero-field magnetic structure of CePtAl4Ge2 is of multi-k wherein symmetry-equivalent three arms of k = (1.39, 0, 0.09) are superposed. Calculating the topological numbers around singular points in a simulated multi-k spin structure shows a non-trivial hedgehog number, indicating that a three-dimensional topological spin texture is realized in this frustrated Kondo lattice. Effective spin Hamiltonian, which contains biquadratic anisotropic interactions controlled by Kondo coupling, successfully explains neutron results, suggesting that the Kondo coupling stabilizes the topological magnetic structure [2]. In this presentation, we will discuss the correlation between Kondo coupling and the topological magnetic phase and the field-induced topological phase transitions of CePtAl4Ge2.
[1] S. Shin et al., Physical Review B 101, 224421 (2020).
[2] S. Shin et al., in preparation