Two-dimensional ferromagnetic spin-orbital excitations in honeycomb VI3

Article

关键词: MAGNETIC EXCITATIONS;    NEUTRON-SCATTERING;    ORDER;    TRANSITION;    DISCOVERY;    WAVES;    IONS;   

DOI  :  10.1103/PhysRevB.104.L020411

来源: SCIE

【 摘 要 】

VI3 is a ferromagnet with planar honeycomb sheets of bonded V3+ ions held together by van der Waals forces. We apply neutron spectroscopy to measure the two-dimensional (J/J(c) approximate to 17) magnetic excitations in the ferromagnetic phase, finding two energetically gapped (Delta approximate to k(B)T(c) approximate to 55 K) and dispersive excitations. We apply a multilevel spin-wave formalism to describe the spectra in terms of two coexisting domains hosting differing V3+ orbital ground states built from contrasting distorted octahedral environments. This analysis fits a common nearest-neighbor in-plane exchange coupling (J = -8.6 +/- 0.3 meV) between V3+ sites. The distorted local crystalline electric field combined with spin-orbit coupling provides the needed magnetic anisotropy for spatially long-ranged two-dimensional ferromagnetism in VI3.

【 授权许可】

Free