Evolution of domain structure with electron doping in ferroelectric thin films

Abstract

To minimize their electrostatic energy, insulating ferroelectric films tend to break up into nanoscale ``Kittel'' domains of opposite polarization that are separated by uncharged 180${}^{\circ }$ domain walls. Here, I report on self-consistent solutions of coupled Landau-Ginzburg-Devonshire and Schrödinger equations for an electron-doped ferroelectric thin film. The model is based on LaAlO${}_3$/SrTiO${}_3$ interfaces in which the SrTiO${}_3$ substrate is made ferroelectric by cation substitution or strain. I find that electron doping destabilizes the Kittel domains. As the two-dimensional electron density $n_{2D}$ increases, there is a smooth crossover to a zigzag domain wall configuration. The domain wall is positively charged, but is compensated by the electron gas, which attaches itself to the domain wall and screens depolarizing fields. The domain wall approaches a flat head-to-head configuration in the limit of perfect screening. The polarization profile may be manipulated by an external bias voltage and the electron gas may be switched between surfaces of the ferroelectric film.

References in corpus (31)

• Electric Field Control of the LaAlO${}_3$/SrTiO${}_3$ Interface Ground State
• Tunable Rashba spin-orbit interaction at oxide interfaces
• Direct imaging of the coexistence of ferromagnetism and superconductivity at the LaAlO3/SrTiO3 interface
• Coexistence of superconductivity and ferromagnetism in two dimensions
• Tuning spin-orbit coupling and superconductivity at the SrTiO3/LaAlO3 interface: a magneto-transport study
• A Universal Critical Density Underlying the Physics of Electrons at the LaAlO3/SrTiO3 Interface
• A ferroelectric quantum phase transition inside the superconducting dome of Sr${}_{1-x}$Ca${}_x$TiO${}_{3-\delta }$
• Origin of the two-dimensional electron gas at LaAlO3/SrTiO3 interfaces: The role of oxygen vacancies and electronic reconstruction
• Critical thickness for ferromagnetism in LaAlO3/SrTiO3 heterostructures
• "Head-to-head" and "tail-to-tail" 180-degree domain walls in an isolated ferroelectric
• Theory of t2g electron-gas Rashba interactions
• Towards two-dimensional metallic behavior at LaAlO3/SrTiO3 interfaces
• Origin of two-dimensional electron gases at oxide interfaces: insights from theory
• First-principles modeling of electrostatically doped perovskite systems
• A Gate-tunable Polarized Phase of Two-Dimensional Electrons at the LaAlO3/SrTiO3 Interface
• Strong correlations elucidate the electronic structure and phase-diagram of LaAlO3/SrTiO3 interface
• Six-fold crystalline anisotropic magnetoresistance in the (111) LaAlO${}_3$/SrTiO${}_3$ oxide interface
• Gate-tunable band structure of the LaAlO${}_3$-SrTiO${}_3$ interface
• Interface superconductivity in LaAlO${}_3$-SrTiO${}_3$ heterostructures
• Artificial two-dimensional polar metal by charge transfer to a ferroelectric insulator
• A switchable two-dimensional electron gas based on ferroelectric Ca:SrTiO${}_3$
• Anisotropic, multi-carrier transport at the (111) LaAlO${}_3$/SrTiO${}_3$ interface
• A Landau Primer for Ferroelectrics
• Ferroelectric Exchange Bias Affects Interfacial Electronic States
• Correlation between Superconductivity, Band Filling and Electron Confinement at the LaAlO${}_3$-SrTiO${}_3$ Interface
• Magnetic and nematic orders of the 2DEG at oxide (111) surfaces and interfaces
• Electrostatics and domains in ferroelectric superlattices
• Influence of the ferroelectric quantum critical point on SrTiO${}_3$ interfaces
• Temperature-Dependent Band Structure of SrTiO${}_3$ Interfaces
• Possible Flexoelectric Origin of the Lifshitz Transition in LaAlO${}_3$/SrTiO${}_3$ Interfaces
• Mechanism for Switchability in Electron-Doped Ferroelectric Interfaces

Cited by in corpus (2)

• Influence of a Realistic Multiorbital Band Structure on Conducting Domain Walls in Perovskite Ferroelectrics
• Dynamics of Conducting Ferroelectric Domain Walls