相关论文: Elasticity of 2D ferroelectrics across their parae…
We use a classical analytical and separable elastic energy landscape describing SnO monolayers to estimate the softening of elastic moduli through a mechanical instability occurring at finite temperature in this material. Although not…
Coordination-related, two-dimensional (2D) structural phase transitions are a fascinating and novel facet of two-dimensional materials with structural degeneracies. Nevertheless, a unified theoretical account of these transitions remains…
We study the elastic energy landscape of two-dimensional tin oxide (SnO) monolayers and demonstrate a transition temperature of $T_c=8.5\pm 1.8$ K using ab-initio molecular dynamics (MD), that is close to the value of the elastic energy…
SnSe monolayers experience a temperature induced two-dimensional Pnm2$_1 \to$ P4/nmm structural transformation precipitated by the softening of vibrational modes. The standard theoretical treatment of thermoelectricity---which relies on a…
One account of two-dimensional (2D) structural transformations in 2D ferroelectrics predicts an evolution from a structure with Pnm2$_1$ symmetry into a structure with square P4/nmm symmetry and is consistent with experimental evidence,…
Two-dimensional (2D) ferroelectric semiconductors present opportunities for integrating ferroelectrics into high-density ultrathin nanoelectronics. Among the few synthesized 2D ferroelectrics, $\alpha$-In$_2$Se$_3$, known for its…
Unlike conventional two-dimensional (2D) semiconductor superlattices, moir\'{e} patterns in 2D materials are flexible and their electronic, magnetic, optical, and mechanical properties depend on their topography. Within a…
Very thin elastic sheets, even at zero temperature, exhibit nonlinear elastic response by virtue of their dominant bending modes. Their behavior is even richer at finite temperature. Here we use molecular dynamics (MD) to study the…
Structural degeneracies underpin the ferroic behavior of next-generation two-dimensional materials, and lead to peculiar two-dimensional structural transformations under external fields, charge doping and/or temperature. The most direct…
We performed density functional theory calculations with self-consistent van der Waals corrected exchange-correlation (XC) functionals to capture the structure of black phosphorus and twelve monochalcogenide monolayers and find the…
A ferroelectric is a material with a polar structure whose polarity can be reversed by applying an electric field. In metals, the itinerant electrons tend to screen electrostatic forces between ions, helping to explain why polar metals are…
Elastic constants of two-dimensional (2D) colloidal crystals are determined by measuring strain fluctuations induced by Brownian motion of particles. Paramagnetic colloids confined to an air-water interface of a pending drop are…
The electronic and thermoelectric properties of one to four monolayers of MoS$_{2}$, MoSe$_{2}$, WS$_{2}$, and WSe$_{2}$ are calculated. For few layer thicknesses,the near degeneracies of the conduction band $K$ and $\Sigma$ valleys and the…
2H phase (trigonal prismatic D3h) of layered two-dimensional (2D) transition metal dichalcogenides (TMDs) have attracted a lot of interests due to the superior electronic and optoelectronic properties. However, flexible electronic devices…
We carried out fully-atomistic reactive molecular dynamics simulations to study the elastic properties and fracture patterns of transition metal dichalcogenide (TMD) MoX2 (X=S, Se, Te) membranes, in their 2H and 1T phases, within the…
A thermodynamic theory of ferroelectric thin film multilayers is developed. The free energy function is written down using a multilayer model in which c-domain layers of one ferroelectric material alternate with a-domain layers of a second…
Recently, the observation of atomic thin film SnTe with a Curie temperature (Tc) higher than that of the bulk (Chang et. al., Science 353, 274 (2016)) has boosted the research on two-dimensional (2D) ferroic materials tremendously. However,…
Two dimensional (2D) layered transition-metal-based tellurides (chalcogens) are known to harness their surface atoms characteristics to enhance topographical activities for energy conversion, storage, and magnetic applications. High surface…
Traditional ferroelectrics undergo thermally-induced phase transitions whereby their structural symmetry increases. The associated higher-symmetry structure is dubbed {\em paraelectric}. Ferroelectric transition metal dichalcogenide…
The properties of two-dimensional (2D) materials have been extensively studied and applied in various applications. Our interest is to theoretically investigate the thermal transport and thermoelectric properties of the 2D transition metal…