Tetrahedral triple-Q magnetic ordering and large spontaneous Hall conductivity in the metallic triangular antiferromagnet Co1/3TaS2

• Published in: Nature communications 2023-12, Vol.14 (1), p.8346-8346, Article 8346
• Main Authors: Park, Pyeongjae, Cho, Woonghee, Kim, Chaebin, An, Yeochan, Kang, Yoon-Gu, Avdeev, Maxim, Sibille, Romain, Iida, Kazuki, Kajimoto, Ryoichi, Lee, Ki Hoon, Ju, Woori, Cho, En-Jin, Noh, Han-Jin, Han, Myung Joon, Zhang, Shang-Shun, Batista, Cristian D., Park, Je-Geun
• Format: Article
• Language: English
• Subjects: 639/301/119/997; 639/766/119/997; Antiferromagnetism; Crystal lattices; Crystal structure; Crystals; Electronic structure; Frustrated magnetism; Hall effect; Humanities and Social Sciences; Hypothetical particles; Inelastic scattering; Insulation; Magnetism; multidisciplinary; Neutron scattering; Neutrons; Nuclear cross sections; Particle theory; Photoelectric emission; Scattering cross sections; Science; Science & Technology - Other Topics; Science (multidisciplinary); Spectroscopy; Structure factor; Wavelength
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-023-43853-4

The triangular lattice antiferromagnet (TLAF) has been the standard paradigm of frustrated magnetism for several decades. The most common magnetic ordering in insulating TLAFs is the 120° structure. However, a new triple- Q chiral ordering can emerge in metallic TLAFs, representing the short wavelength limit of magnetic skyrmion crystals. We report the metallic TLAF Co 1/3 TaS 2 as the first example of tetrahedral triple- Q magnetic ordering with the associated topological Hall effect (non-zero σ xy ( H  = 0)). We also present a theoretical framework that describes the emergence of this magnetic ground state, which is further supported by the electronic structure measured by angle-resolved photoemission spectroscopy. Additionally, our measurements of the inelastic neutron scattering cross section are consistent with the calculated dynamical structure factor of the tetrahedral triple- Q state. Skyrmion crystals, where skyrmions are arranged close packed in a triangular lattice arise due to the superposition of three magnetic spin spirals, each with a distinct wave vector, Q. Such skrymion crystals have been found in a diverse array of materials. Here, Park et al find a short wavelength (or dense skyrmion) limit of this skyrmion crystal structure in Co1/3TaS2, a metallic triangular lattice antiferromagnet, in the form of a triple Q magnetic ordering, with four magnetic sublattices.’