相关论文: Direct observation of the layer-number-dependent e…
Single crystal tungsten ditelluride (WTe2) has recently been discovered to exhibit non-saturating extreme magnetoresistance in bulk; it has also emerged as a new layered material from which atomic layer crystals can be extracted. While…
WTe2, as a type-II Weyl semimetal, has 2D Fermi arcs on the (001) surface in the bulk and 1D helical edge states in its monolayer. These features have recently attracted wide attention in condensed matter physics. However, in the…
A unique attribute of atomically thin quantum materials is the in-situ tunability of their electronic band structure by externally controllable parameters like electrostatic doping, electric field, strain, electron interactions, and…
The first switchable electric polarization in metals was recently discovered in bilayer and trilayer WTe2. Strangely, despite the tininess of the ordered polarization, the ferroelectricity survives up to 350 K, rendering the mechanism of…
Convergent beam electron diffraction is routinely applied for studying deformation and local strain in thick crystals by matching the crystal structure to the observed intensity distributions. Recently, it has been demonstrated that CBED…
We use density functional theory to calculate the electronic band structures, cohesive energies, phonon dispersions, and optical absorption spectra of two-dimensional In$_2$X$_2$ crystals, where X is S, Se, or Te. We identify two…
We investigate ferroelectric polariation as well as the formation of long-range order and the carrier density distribution in type-II Weyl semimetal WTe$_{2}$ in $T_{d}$ phase. It is been found that the metallicity and ferroelectricity can…
The interlayer coupling is emerging as a new parameter for tuning the physical properties of two-dimensional (2D) van der Waals materials. When two identical semiconductor monolayers are stacked with a twist angle, the periodic interlayer…
Since the discovery of large, non-saturating magnetoresistance in bulk WTe2 which allows microexfoliation, single- and few-layer WTe2 crystals have attracted increasing interests. However, as it mentioned in existing studies, WTe2 flakes…
Electron-phonon scatterings in solid-state systems are pivotal processes in determining many key physical quantities such as charge carrier mobilities and thermal conductivities. Here, we report on the direct probing of phonon mode specific…
The dielectric constant or relative permittivity of a dielectric material, which describes how the net electric field in the medium is reduced with respect to the external field, is a parameter of critical importance for charging and…
The crystal structure of a material creates a periodic potential that electrons move through giving rise to the electronic band structure of the material. When two-dimensional materials are stacked, the twist angle between the layers…
The electronic structure of the unconventional superconductor UTe$_2$ was studied by resonant photoelectron spectroscopy (RPES) and angle-resolved photoelectron spectroscopy (ARPES) with soft X-ray synchrotron radiation. The partial…
Most non-ferroelectric two-dimensional materials can be endowed with so-called sliding ferroelectricity via non-equivalent homo-bilayer stacking, which is not applicable to mono-element systems like pure graphene bilayer with inversion…
Low-dimensional electron systems, as realized naturally in graphene or created artificially at the interfaces of heterostructures, exhibit a variety of fascinating quantum phenomena with great prospects for future applications. Once…
Graphene and few-layer graphene at high bias expose a wealth of phenomena due to the high temperatures reached. With in-situ transmission electron microscopy (TEM) we observe directly how the current modifies the structure, and vice versa.…
Due to the strong quantum confinement effect, few-layer {\gamma}-InSe exhibits a layer-dependent bandgap, spanning the visible and near infrared regions, and thus recently draws tremendous attention. As a two-dimensional material, the…
Twisted bilayer transition metal dichalcogenides, such as MoTe$_2$, provide a versatile platform for exploring correlated topological phases. This work investigates the interplay of perpendicular magnetic and electric fields in tuning the…
A new frontier in condensed matter physics is to stack atomically thin layered-materials with different properties and create intriguing phenomena which do not exist in any of the constituent layers. Transition metal dichalcogenide…
The layered material ZrTe$_5$ appears to exhibit several exotic behaviors which resulted in significant interest recently, although the exact properties are still highly debated. Among these we find a Dirac/Weyl semimetallic behavior,…