Non-stoichiometry, defect structure, and dielectric relaxation in lanthana-substituted SrTiO3

Dielectric relaxation modes in bismuth-doped SrTiO3: The relaxor behavior

The ferroelectric relaxor behavior in Bi-doped SrTiO3 was studied in the temperature range 1.5–300 K and up to 400 MHz. Some interesting results are shown: ~1! Typical ferroelectric relaxor behavior develops out of the other impurity relaxation modes. The ferroelectric relaxor peaks occur on the quantum-paraelectric background. The polarization irreversibility effect observed after field coolin...

Defect Diffusion Models in NMR and Dielectric Relaxation

Defect diffusion has proven to be a good tool in many cases to solve the problem arising when molecular motions are not describable by expo­ nential correlation functions i.e. as Poisson proc­ esses. Thus a series of models and applications can be found in literature [1 — 6 ] concerning continuous or step-wise diffusion mechanism with and without restriction. On the other hand there is the poss...

Surface and defect structure of oxide nanowires on SrTiO3.

Processing the SrTiO(3)(001) surface results in the self-assembly of reduced titanate nanowires whose widths are approximately 1 nm. We have imaged these nanowires and their defects at elevated temperatures by atomic resolution scanning tunneling microscopy. The nanowire structure is modeled with density functional theory, and defects observed in the center of the nanowire are determined to be ...

Dielectric relaxation and conduction in SrTiO3 thin films under dc bias

The dielectric and conduction behavior of SrTiO3 thin films deposited on a SrTiO3 single-crystal substrate is studied. Without dc bias, an obvious dielectric ‘‘defect mode’’ in the dielectric loss is observed in the temperature range of ;100–200 K; however, no noticeable corresponding dielectric constant peak is observed. By applying a high dc bias ~>40 kV/cm!, a dielectric constant peak with f...

Dielectric Properties of Ultrathin SrTiO3 and Metal-SrTiO3 Interfaces