Pressure-induced transformations of multiferroic relaxor PbFe0.5Nb0.5O3
Abstract
The effects of hydrostatic pressure at ambient temperature on the structural and dielectric properties of PbFe0.5Nb0.5O3 (PFN) were investigated using second harmonic generation (SHG) and powder x-ray diffraction measurements to 31 GPa. The results demonstrate that PFN undergoes a pressure-induced structural transition from the R3m ferroelectric to the R3¯m paraelectric phase. SHG measurements showed a continuous decrease in the signal with pressure and complete disappearance at 7.1 GPa. Effective nonlinear optical coefficients were determined from the SHG data, and their pressure behavior was used to infer the nature of the transition. The loss of the SHG signal is accompanied by drastic changes in line widths of Bragg reflections, but no discontinuous change in volume was observed. The pressure-volume data were fit to various equations of state, and a bulk modulus K0 = 136 (±2) GPa, bulk modulus pressure derivative K0′ = 4.0 (±0.2), and initial volume V0 = 64.5 (±0.1) Å3 were obtained.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 26, 2018
- Source ID
- 10.1063/1.5019485
Entities
People
- Abhisek Basu
- Chuanlong Lin
- Muhtar Ahart
- Nicholas Holtgrewe
- Russell J. Hemley
Organizations
- Carnegie Institution for Science
- George Washington University
- Howard University
- National Science Foundation
- Office of Naval Research
- United States Department of Energy