Low-temperature structural and Raman studies on rare-earth gallates

Abstract

Measurements of lattice parameters and structural refinement were made for a LaGaO 3 , PrGaO 3 , NdGaO 3 , La 0.34 Pr 0.33 Nd 0.33 GaO 3 , and La 0.63 Nd 0.37 GaO 3 samples by powder-diffraction method using synchrotron radiation. The final structure refinement was performed in space group Pbnm at 12 K and room temperature. Anisotropic negative thermal expansion for PrGaO 3 samples was detected. Some anomalies of NdGaO 3 thermal behavior of lattice parameters were observed. The thermal dependence of the Raman spectra of NdGaO 3 single crystals at low temperatures was investigated. Strong interaction of the A g phonon and the crystal-field excitation of the Nd 3ϩ 4 f electrons of the same symmetry was observed. This leads to a renormalization of the wave function and the energy of the phonon and the crystal-field excitation.

Electric field driven dynamic percolation in electronically phase separated (La0.4Pr0.6)Jeen1, Biswas2 2013Phys. Rev. B321310View full textAdd to dashboardCite

“…show that the in-plane magnetic anisotropy does not switch directions over the temperature range of this study, which is consistent with the fact that NGO does not show a structural transition in this temperature range [22] and that the average in-plane lattice contant of LPCMO is locked to the NGO substrate as the temperature is changed [18]. For the unpatterned thin films, the magnetic anisotropy does not lead to anisotropic resistivity [17].…”

Thermal expansion of the perovskite-type NdGaO3

“…[5]. For high-temperature (HT) structural investigations, the powder diffractometer at beamline B2 (HASYLAB/DESY) was used.…”

Multiferroic Domain Boundaries as Active Memory Devices: Trajectories Towards Domain Boundary Engineering

“…The largest component is the one along the z direction antiferroelectric with alternating Ti positions shifted in opposite directions. In contrast, the off-centering along the y direction is ferroelectric and produces a net dipole moment for The thickness of the interface is 2w~6 unit layers or~2.3 nm [15] (photograph courtesy G. Van Tendeloo, Antwerp).…”