2009/08/26 by Kunihiko Yamauchi, Silvia Picozzi
Chemistry · Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Anisotropy #Atomic physics #Chemistry #Condensed matter physics #Ferroelectric and Piezoelectric Materials #Ground state #Magnetic anisotropy #Magnetic field #Magnetization #Materials science #Multiferroics and related materials #Physical chemistry #Physics #Polarization (electrochemistry) #Quantum mechanics #Spin (aerodynamics) #Thermodynamics #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.81.024110
4 pages, 4 figures. Submitted for publication
arxiv created 2009/08/26 · openalex publication_date 2010/01/21 · arxiv updated 2015/05/14 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Li-based phosphates are paradigmatic materials for magnetoelectricity. By means of first-principles calculations, we elucidate the microscopic origin of spin anisotropy and of magnetoelectric effects in LiNiPO4. The comparison with LiCoPO4 reveals that Co d7 and Ni d8 electronic clouds show distinct orbital shapes, which in turn result in an opposite trend of the local spin anisotropy with respect to the surrounding O6 cages. Due to magnetic anisotropy, the Ni-based phosphate shows a peculiar ``angled-cross'' spin ground state, which is responsible for magnetoelectricity. In this respect, we show that, under a magnetic field Hx, an electronic polarization Pz arises, with an estimated linear magnetoelectric coefficient in good agreement with experiments.