Electronic and magnetic structure ofRScO3(R=Sm,Gd,Dy) from x-ray spectroscopies and first-principles calculations

Structure of singly terminated polar DyScO3(110) surfaces

“…22 Insulating DyScO 3 easily charges in an electron beam at room temperature and high vacuum due to its large band gap (5.9 eV), complicating RHEED measurements. 2 Therefore the measurements were performed at 10 −3 mbar O 2 to reduce surface charging. Figure 4 shows the diffraction patterns along the different DyScO 3 (001) pc surface directions, measured at room temperature using 30 keV electrons.…”

First-principles study of intermixing and polarization at the DyScO3/SrTiO3interface

“…17 As parameters we chose U = 10.8 eV and J = 0.68 eV, values from the literature. 18 Self-consistency was considered to be achieved when the total energy variation from iteration to iteration did not exceed 3 × 10 −5 eV and forces on the atoms were converged to 50 meV/Å. The reciprocal space was sampled by a mesh containing 40 k points [corresponding to an (8 × 8 × 8) Monkhorst-Pack mesh] in the irreducible wedge of the Brillouin zone for the cubic phases, and an equivalently dense k-point sampling for the supercells.…”

“…In this setup, the band gap was found to be 4.47 eV, in good agreement with previous calculations and about 24% smaller than the experimentally observed value. 18 Given a SrTiO 3 (001) substrate, there are different models how an interface with DyScO 3 can be formed. Considering the experimental SrTiO 3 lattice parameter of 3.905Å, a c(2 × 2) in-plane unit cell, that is, a centered, square cell containing two formula units, fits to the DyScO 3 (001) surface if the a and b parameters are expanded or contracted by 1.5% and 3.5%, respectively.…”

Reconstructions at complex oxide interfaces

“…REScO 3 are highly insulating, with an optical bandgap > 5.5 eV. [38] The scandates are paramagnetic at room temperature and have a magnetic phase transition to antiferromagnetic long range order at low temperatures; for DyScO 3 at 3.1 K. [38,39] A strong magnetic anisotropy was observed with an easy axis along the [100] direction and a hard axis along the [001] direction. [39] It is also suggested that REScO 3 have high dielectric constants, but this is only reported for REScO 3 thin films.…”

“…Insulating DyScO 3 easily charges in an electron beam at room temperature and high vacuum due to its large bandgap (5.9 eV), complicating RHEED measurements. [38] Therefore, the measurements were done in 10 −3 mbar oxygen to reduce surface charging; the O 2 background gas acts as a charge neutralizer. [10] directions were observed, which implies an in-plane four-fold symmetry.…”