Artificial superlattices made from a ferroelectric and a paraelectric oxide are studied, and a new kind of atom rearrangement is found to take place at the interfaces between thin films of these materials, leading to an unusual, 'improper' ferroelectric effect. As a result, the system has a very large dielectric constant that, in contrast to conventional ferroelectricity, is fairly temperature independent; this observation is of considerable interest for practical applications.
- Eric Bousquet
- Matthew Dawber
- Philippe Ghosez
