Ferroelectric polymers in multiferroic heterostructures and field-effect devices 1 I. Stolichnov1* Laboratory of Ceramics, EPFL - Swiss Federal Institute of Technology LC-IMX-STI-EPFL, Station 12, Lausanne 1015, Switzerland *e-mail: [email protected] Ferroelectric polymers offer a viable solution to overcome the issue of integration of ferroelectric gate on a great variety of systems potentially useful for functional electronics. The copolymers of polyvinylidene fluoride and trifluoroethylene P(VDF-TrFE) are of particular interest because of their relatively high remanent polarization, low dielectric permittivity, low processing temperature and chemical stability. Ferroelectric field effect have been successfully demonstrated using P(VDF-TrFE) gates integrated on Si, graphene and semiconductor heterostructures such as AlGaN/GaN. Further to the field effect transistor concept ferroelectric polymer gates show a strong promise for non-volatile ferroelectric control of ferromagnetism. Recently demonstrated persistent ferroelectric field effect on domain walls in ferromagnets offers an alternative to well-established domain manipulation techniques based on spin-torque transfer. The integrated ferromagnet/ferroelectric structures yield two superimposed ferroic patterns coupled by electric field. Using this coupling a stable, non-destructive, and electrically re-writable switch on magnetic domain wall propagation has been demonstrated. In proof-of-concept experiments the regimes where the ferroelectric domains enhance/inhibit the magnetic domain nucleation, increase/reduce domain wall velocity or block domain growth have been demonstrated on different materials including metals (cobalt) at room temperature. Curriculum Vitae Igor Stolichnov received his diploma in physics at Saint-Petersburg Technical University in 1993. Since 1996 he has been working at EPFL (Swiss Federal institute of Technology, Lausanne) where he was awarded PhD in Technical Sciences in 2000. Currently he is a Senior Researcher at Ceramics Laboratory, EPFL, where he is leading a group working on ferroelectric and multiferroic thin films and heterostructures. His current research interests include ferroelectricferromagnetic heterostructures, functional properties of ferroic domain walls, ferroelectric polymer thin films and nanostructures.
© Copyright 2024