相关论文: Structural Polymorphism Kinetics Promoted by Charg…
In-situ diffuse neutron scattering experiments revealed that when electric current is passed through single crystals of rutile TiO2 under conditions conducive to flash sintering, it induces the formation of parallel planes of oxygen…
Hf0.5Zr0.5O2 (HZO) is a promising candidate for next generation ferroelectric memories and transistors. However, its ferroelectricity origin is still under debate due to the complex of its phase and microstructure in practical samples. In…
Unknown changes in the crystalline order of regular TiO$_2$ result in the formation of black titania, which has garnered significant interest as a photocatalytic material due to the accompanying electronic changes. Herein, we determine the…
By using DFT+U, we explore the formation of oxygen vacancies and their impact on the electronic and magnetic structure in strained bulk LaNiO3 and (LaNiO3)$_1$/(LaAlO3)$_1$(001) superlattices. For bulk LaNiO3, we find that epitaxial strain…
Ferroelectric memories experienced a revival in the last decade due to the discovery of ferroelectricity in HfO$_2$-based nanometer-thick thin films. These films exhibit exceptional silicon compatibility, overcoming the scaling and…
Oxygen plays a critical role in strongly correlated transition metal oxides as crystal field effect is one of the key factors that determine the degree of localization of the valence d/f states. Based on the localization, a set of…
The discovery of ferroelectricity in HfO$_2$-based thin films opens up new opportunities for using this silicon-compatible ferroelectric to realize low-power logic circuits and high-density non-volatile memories. The functional performances…
Thickness driven electronic phase transitions are broadly observed in different types of functional perovskite heterostructures. However, uncertainty remains whether these effects are solely due to spatial confinement, broken symmetry or…
In hafnia-based thin-film ferroelectric devices, chemical phenomena during growth and processing such as oxygen vacancy formation and interfacial reactions appear to strongly affect device performance. However, the nanoscale structure,…
Oxygen vacancies, especially their distribution, are directly coupled to the electromagnetic properties of oxides and related emergent functionalities that have implication in device applications. Here using a homoepitaxial strontium…
We show that oxygen vacancies at titanate interfaces induce a complex multiorbital reconstruction which involves a lowering of the local symmetry and an inversion of t2g and eg orbitals resulting in the occupation of the eg orbitals of Ti…
The structure-property relation of nanostructured Al-doped ZnO thin films has been investigated in detail through a systematic variation of structure and morphology, with particular emphasis on how they affect optical and electrical…
While defects such as oxygen vacancies in correlated materials can modify their electronic properties dramatically, understanding the microscopic origin of electronic correlations in materials with defects has been elusive. Lanthanum…
With the broad recent research on ferroelectric hafnium oxide for non-volatile memory technology, depolarization effects in HfO2-based ferroelectric devices gained a lot of interest. Understanding the physical mechanisms regulating the…
Using density-functional theory with ultrasoft pseudopotentials, we previously investigated the structural and electronic properties of the low-pressure (cubic, tetragonal, and monoclinic) phases of ZrO2 and HfO2, in order to elucidate…
We perform ab initio calculations, based on density functional theory, of substitutional and vacancy defects in the monoclinic hafnium oxide (m-HfO2) and alpha-quartz (SiO2). The neutral oxygen vacancies and substitutional Si and Hf defects…
Flexoelectricity, inherent in all materials, offers a promising alternative to piezoelectricity for nanoscale actuation and sensing. However, its widespread application faces significant challenges: differentiating flexoelectric effects…
Kinetic of a reversible structural transition between insulating (2H) and metallic (1T') phases in a monolayer MoTe2 due to an electrostatic doping is studied using first-principle calculations. The driving force for the structural…
The observation of metallic interface between band insulators LaAlO$_3$ and SrTiO$_3$ has led to massive efforts to understand the origin of the phenomenon as well as to search for other systems hosting such two dimensional electron gases…
Intertwined ionic conduction and ferroelectric (FE) switching in HfO2 lead to extensive focuses. To describe its fundamental phenomena, we present a free-energy model describing the potential of ferroelectrics with successive FE switching…