相关论文: Pathways Towards Ferroelectricity in Hafnia

We use a combination of symmetry analysis and high-throughput density functional theory calculations to search for new ferroelectric materials. We use two search strategies to identify candidate materials. In the first strategy, we start…

We have investigated the magnetic and dielectric properties of orthorhombic Eu$_{1-y}$Y$_y$MnO$_3$ ($0\leq y\leq 0.6$) single crystals without the presence of the 4$f$ magnetic moments of the rare-earth ions. In $y\geq 0.2$, the…

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…

The discovery of ferroelectric HfO2 in thin films and more recently in bulk is an important breakthrough because of its silicon-compatibility and unexpectedly persistent polarization at low dimensions, but the origin of its ferroelectricity…

Ferroelectric hafnia is being explored for next generation electronics due to its robust ferroelectricity in nanoscale samples and its compatibility with silicon. However, its ferroelectricity is not understood. Other ferroelectrics usually…

Using first-principles methods, we predict the energy landscape and ferroelectric states of double perovskites of the form AA$'$BB$'$O$_6$ in which the atoms on both the A and B sites are arranged in rock-salt order. While we are not aware…

Hafnia (HfO2) is a promising material for emerging chip applications due to its high-k dielectric behaviour, suitability for negative capacitance heterostructures, scalable ferroelectricity, and silicon compatibility. The lattice dynamics…

Ferroelectricity observed in thin film $\mathrm{HfO_2}$, either doped with Si, Al, etc. or in the $\mathrm{Hf_{0.5}Zr_{0.5}O_2}$ form, has gained great technical significance. However, the soft mode theory faces a difficulty in explaining…

Ferroelectricity in the complementary metal-oxide semiconductor (CMOS)-compatible hafnia (HfO$_2$) is crucial for the fabrication of high-integration nonvolatile memory devices. However, the capture of ferroelectricity in HfO$_2$ requires…

Ferroelectrics and ionic conductors are important functional materials, each supporting a plethora of applications in information and energy technology. The underlying physics governing their functional properties is ionic motion, and yet…

The metastable nature of the ferroelectric phase of HfO$_2$ is a significant impediment to its industrial application as a functional ferroelectric material. In fact, no polar phases exist in the bulk phase diagram of HfO$_2$, which shows a…

We analyze a system of polar molecules in a one-dimensional optical lattice. By controlling the internal structure of the polar molecules with static electric and microwave fields, we demonstrate the appearance of a quantum phase transition…

We performed density functional theory (DFT) calculations on epitaxially strained hafnia. We demonstrate the stabilization of the ferroelectric ($Pca2_{1}$) phase from the antiferroelectric ($Pbcn$) in bulk hafnia in the presence of…

A comparative theoretical study is presented for the rhombohedral R3 and R3m phase HfO2, of two possible forms in its heavily Zr-doped ferroelectric thin films found recently in experiments. Their structural stability and polarization under…

In this work, we propose a class of ferroelectrics (which we denote "double-path" ferroelectrics), characterized by two competing polarization switching paths for which the change in polarization is different and in fact of opposite sign.…

Antiferroelectricity is a material property characterized by alternating electric dipoles spontaneously ordered in antiparallel directions. Antiferroelectrics are promising for energy storage, solid-state cooling, and memory technologies;…

We study the free energy landscape of a minimal model for relaxor ferroelectrics. Using a variational method which includes leading correlations beyond the mean-field approximation as well as disorder averaging at the level of a simple…

HfO2, a simple binary oxide, holds ultra-scalable ferroelectricity integrable into silicon technology. Polar orthorhombic (Pbc21) form in ultra-thin-films ascribes as the plausible root-cause of the astonishing ferroelectricity, which has…

Defects such as oxygen vacancy are widely considered to be critical for the performance of HfO2-based devices, and yet atomistic mechanisms underlying various exotic effects such as wake-up and fluid imprint remain elusive. Here, guided by…

Ferroelectric HfO$_2$ has emerged as a highly promising material for high-density nonvolatile memory and nanoscale transistor applications. However, the uncertain origin of polarization in HfO$_2$ limits our ability to fully understand and…