Thermotropic phase boundaries in classic ferroelectrics

T.T.A. Lummen, Y. Gu, J. Wang, S. Lei, F. Xue, A. Kumar, A.T. Barnes, E. Barnes, S. Denev, A. Belianinov, M. Holt, A.N. Morozovska, S.V. Kalinin, L.-Q. Chen, V. Gopalan

Research output: Contribution to journalArticlepeer-review

85 Citations (Scopus)
297 Downloads (Pure)


High-performance piezoelectrics are lead-based solid solutions that exhibit a so-called morphotropic phase boundary, which separates two competing phases as a function of chemical composition; as a consequence, an intermediate low-symmetry phase with a strong piezoelectric effect arises. In search for environmentally sustainable lead-free alternatives that exhibit analogous characteristics, we use a network of competing domains to create similar conditions across thermal inter-ferroelectric transitions in simple, lead-free ferroelectrics such as BaTiO 3 and KNbO 3. Here we report the experimental observation of thermotropic phase boundaries in these classic ferroelectrics, through direct imaging of low-symmetry intermediate phases that exhibit large enhancements in the existing nonlinear optical and piezoelectric property coefficients. Furthermore, the symmetry lowering in these phases allows for new property coefficients that exceed all the existing coefficients in both parent phases. Discovering the thermotropic nature of thermal phase transitions in simple ferroelectrics thus presents unique opportunities for the design of 'green' high-performance materials.
Original languageEnglish
Article number3172
JournalNature Communications
Publication statusPublished - 20 Jan 2014

Fingerprint Dive into the research topics of 'Thermotropic phase boundaries in classic ferroelectrics'. Together they form a unique fingerprint.

Cite this