6 Ferroelectric polarization in multiferroics
-
Stephan Krohns
and Peter Lunkenheimer
Abstract
Multiferroic materials, showing ordering of both electrical and magnetic degrees of freedom, are promising candidates enabling the design of novel electronic devices. Various mechanisms ranging from geometrically or spin-driven improper ferroelectricity via lone-pairs, charge-order or -transfer support multiferroicity in singlephase or composite compounds. The search for materials showing these effects constitutes one of the most important research fields in solid-state physics during the last years, but scientific interest even traces back to the middle of the past century. Especially, a potentially strong coupling between spin and electric dipoles captured the interest to control via an electric field the magnetization or via a magnetic field the electric polarization. This would imply a promising route for novel electronics. Here, we provide a review about the dielectric and ferroelectric properties of various multiferroic systems ranging from type I multiferroics, in which magnetic and ferroelectric order develop almost independently of each other, to type II multiferroics, which exhibit strong coupling of magnetic and ferroelectric ordering. We thoroughly discuss the dielectric signatures of the ferroelectric polarization for BiFeO3, Fe3O4, DyMnO3 and an organic charge-transfer salt as well as show electric-field poling studies for the hexagonal manganites and a spin-spiral system LiCuVO4.
Abstract
Multiferroic materials, showing ordering of both electrical and magnetic degrees of freedom, are promising candidates enabling the design of novel electronic devices. Various mechanisms ranging from geometrically or spin-driven improper ferroelectricity via lone-pairs, charge-order or -transfer support multiferroicity in singlephase or composite compounds. The search for materials showing these effects constitutes one of the most important research fields in solid-state physics during the last years, but scientific interest even traces back to the middle of the past century. Especially, a potentially strong coupling between spin and electric dipoles captured the interest to control via an electric field the magnetization or via a magnetic field the electric polarization. This would imply a promising route for novel electronics. Here, we provide a review about the dielectric and ferroelectric properties of various multiferroic systems ranging from type I multiferroics, in which magnetic and ferroelectric order develop almost independently of each other, to type II multiferroics, which exhibit strong coupling of magnetic and ferroelectric ordering. We thoroughly discuss the dielectric signatures of the ferroelectric polarization for BiFeO3, Fe3O4, DyMnO3 and an organic charge-transfer salt as well as show electric-field poling studies for the hexagonal manganites and a spin-spiral system LiCuVO4.
Chapters in this book
- Frontmatter I
- Preface V
- Contents VII
- List of Contributing Authors XIII
- 1 A short history of multiferroics 1
- 2 Spin dynamics, antiferrodistortion and magnetoelectric interaction in multiferroics. The case of BiFeO3 13
- 3 Hexagonal manganites: Strong coupling of ferroelectricity and magnetic orders 37
- 4 Spiral spin structures and skyrmions in multiferroics 89
- 5 Non-collinear magnetism & multiferroicity: the perovskite case 127
- 6 Ferroelectric polarization in multiferroics 159
- 7 Probing local order in multiferroics by transmission electron microscopy 193
- 8 Controlling of light with electromagnons 249
- 9 Dynamical magnetoelectric phenomena of skyrmions in multiferroics 271
- 10 Magneto-electric multiferroics: designing new materials from first-principles calculations 293
- 11 Domains and domain walls in multiferroics 335
- 12 Multiferroic heterostructures for spintronics 371
- Index 413
Chapters in this book
- Frontmatter I
- Preface V
- Contents VII
- List of Contributing Authors XIII
- 1 A short history of multiferroics 1
- 2 Spin dynamics, antiferrodistortion and magnetoelectric interaction in multiferroics. The case of BiFeO3 13
- 3 Hexagonal manganites: Strong coupling of ferroelectricity and magnetic orders 37
- 4 Spiral spin structures and skyrmions in multiferroics 89
- 5 Non-collinear magnetism & multiferroicity: the perovskite case 127
- 6 Ferroelectric polarization in multiferroics 159
- 7 Probing local order in multiferroics by transmission electron microscopy 193
- 8 Controlling of light with electromagnons 249
- 9 Dynamical magnetoelectric phenomena of skyrmions in multiferroics 271
- 10 Magneto-electric multiferroics: designing new materials from first-principles calculations 293
- 11 Domains and domain walls in multiferroics 335
- 12 Multiferroic heterostructures for spintronics 371
- Index 413