Electric-field-induced phase transition and pinched P-E hysteresis loops in Pb-free ferroelectrics with a tungsten bronze structure

0492452 - FZÚ 2019 RIV JP eng J - Journal Article
Li, K. - Zhu, X.L. - Liu, X.Q. - Ma, X. - Fu, M.S. - Kroupa, Jan - Kamba, Stanislav - Chen, X.M.
Electric-field-induced phase transition and pinched P-E hysteresis loops in Pb-free ferroelectrics with a tungsten bronze structure.
NPG Asia Materials. Roč. 10, Apr (2018), 1-11, č. článku 71. ISSN 1884-4049. E-ISSN 1884-4057
R&D Projects: GA MŠMT(CZ) LD15014; GA ČR GA15-08389S
Institutional support: RVO:68378271
Keywords : ferroelectrics * antiferroelectrics * incommensurate ferroelectrics domains * second harmonic generation
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 8.052, year: 2018

We report the discovery of pinched, polarization-vs.-electric field (P-E) hysteresis loops in the lead-free tungsten bronze ferroelectrics Ba4Sm2Ti4Nb6O30 and Ba4Eu2Ti4Nb6O30, while a broad, single P-E hysteresis loop was observed in the analogue compound Ba4Nd2Ti4Nb6O30. Pinched P-E loops are similar to antiferroelectric hysteresis loops, but in perovskites, they are mostly caused by an extrinsic, internal bias field due to defects, which block domain wall motion. We show that the pinched P-E loops are caused by an intrinsic effect, i.e., by the electric-field-induced phase transition from a non-polar incommensurate to a polar commensurately modulated crystal structure.
Permanent Link: http://hdl.handle.net/11104/0285986