Ferroelectricity in oxygen-deficient perovskite-type oxide Sr10Ga6Sc4O25

We have investigated the physical properties of an oxygen-deficient perovskite-type Sr10Ga6Sc4O25 by means of dielectric permittivity, pyroelectric current, and X-ray diffraction (XRD) measurements using a polycrystalline sample. The real part of the dielectric permittivity shows a clear anomaly around 310 K. Switchable pyroelectric current is also observed around this temperature, indicating a ferroelectric phase transition in the title compound. Synchrotron powder XRD measurements reveal that no discontinuous jump takes place in the temperature dependent cell volume around 310 K, implying that the phase transition is of second order. The candidates of the low and high temperature space groups are discussed based on the group theory.

Automated summary

We investigated the physical properties of oxygen-deficient perovskite-type Sr10Ga6Sc4O25 by measuring dielectric permittivity, pyroelectric current, and X-ray diffraction (XRD) using a polycrystalline sample. The dielectric permittivity showed an anomaly at around 310 K, and switchable pyroelectric current indicated a ferroelectric phase transition. XRD measurements revealed that the phase transition was of second order, without a discontinuous jump in cell volume. The possible low and high temperature space groups were discussed based on group theory.