Journal
APPLIED PHYSICS LETTERS
Volume 96, Issue 3, Pages -Publisher
AMER INST PHYSICS
DOI: 10.1063/1.3292209
Keywords
ceramics; commensurate-incommensurate transformations; cooling; crystal structure; dielectric relaxation; europium compounds; ferroelectric transitions; heating; hysteresis; permittivity; samarium compounds; strontium compounds; titanium compounds
Categories
Funding
- National Science Foundation of China [90922024, 50832005]
Ask authors/readers for more resources
Sr4R2Ti4Nb6O30 (R=Sm and Eu) tungsten bronze ceramics were prepared, and the dielectric properties and ferroelectric transition were investigated together with the crystal structure. A ferroelectric transition peak and a low temperature dielectric relaxation were observed from the curve of permittivity versus temperature during heating process for both ceramics. The ferroelectric transition indicated large thermal hysteresis during the heating and cooling cycles for both ceramics, where the ferroelectric transition peak disappeared during the cooling process, and the low temperature dielectric relaxation was obviously enhanced. Moreover, extremely large depression of the Curie-Weiss temperature (T-0) was observed in the present ceramics. These abnormal features were associated with the complex tetragonal tungsten bronze structure with two ferroelectrically active cations over two sets of sites and weak superstructure change from incommensurate to commensurate on cooling. The low temperature dielectric relaxation was due to the oxygen octahedron rotation in the ab plane and the possible compositional variations in the microscale.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available