Related papers: Origin of Pyroelectricity in LiNbO3
The perovskite crystal BaTiO3 is modeled using a first-principles based effective Hamiltonian and molecular dynamics simulations are performed to estimate the pyroelectric response. The electrocaloric temperature change, \DeltaT, is…
Pyroelectricity is a very promising phenomenon in three- and two-dimensional (2D) materials, but first-principles calculations have not so far been used to elucidate the underlying mechanisms. Here we report density-functional theory (DFT)…
Pyroelectricity refers to the accumulation of charges due to changes in the spontaneous polarization of ferroelectric materials when subjected to temperature variations. Typically, these pyroelectric charges are considered unstable and…
We describe here the first comprehensive investigation of a pyroelectric response of a p-n junction in a non-polar paraelectric semiconductor. The pyroelectric effect is generated by the, temperature dependent, built-in electrical dipole…
The second and third order nonlinear susceptibilities of the ferroelectric oxides LiNbO$_3$, LiTaO$_3$, and KNbO$_3$ are calculated from first principles. Two distinct methodologies are compared, one approach is based on a perturbative…
(00l)-Oriented LiNbO3 ultra-thin film was fabricated on Pt/Ti/SiO2/Si substrate using pulsed laser deposition. The film shrunk into crystalline state nanoparticles that still kept (00l) preferential orientation as being annealed in the…
We present a method of measuring the charge density on dielectric surfaces. Similar to electrostatic force microscopy we record the electrostatic interaction between the probe and the sample surface, but at large tip-sample distances. For…
Linear dielectric thermodynamics are formally developed to explore the isothermal and adiabatic temperature - pressure dependence of dielectric constants. The refractive index of optical materials is widely measured in the literature: it is…
Self-focusing, spatially stable, electron beams arising from heating up to 160 degrees C and cooling to room temperature pyroelectric LiNbO3 crystals in dilute gases have been observed for the first time. The current (up to nanoamperes) and…
Thermoelectric materials, enabling the directing conversion between heat and electricity, are one of the promising candidates for overcoming environmental pollution and the upcoming energy shortage caused by the over-consumption of fossil…
We have measured the dielectric constant and the pyroelectric current of orthorhombic (space group $Pbam$) NdCrTiO$_5$ polycrystalline samples. The dielectric constant and the pyroelectric current show features associated with ferroelectric…
The principal fact that the pyroelectric vector $\Pb^0$ typical of polar crystals is invisible in equilibrium has been verified. Nevertheless, the general formula for $\Pb^0$ as a definite bulk quantity associated only with the inversion…
Density-functional theory within a Berry-phase formulation of the dynamical polarization is used to determine the second-order susceptibility $\chi^{(2)}$ of lithium niobate (LiNbO$_3$). Defect trapped polarons and bipolarons are found to…
We report here the first observation of a pyroelectric effect in a non-polar semiconductor. This effect originates in the temperature dependent electric dipole of the p-n junction. The junction was illuminated by a chopped CO2 laser beam,…
In this work, we have performed a comprehensive study of dielectric materials NbOX2 (X=Cl, Br, and I) within the framework of density functional theory, incorporating both conventional and hybrid functionals.Our studies focus on the…
We propose a phenomenological theory working out light illumination effects on the equilibrium values of any macroscopic crystal tensor (polarization, magnetization, susceptibilities, strain tensor, elastic coefficients...). it also…
Pyroelectric energy converter is a functional capacitor using pyroelectric material as the dielectric layer. Utilizing the first-order phase transformation of the material, the pyroelectric device can generate adequate electricity within…
We discuss and present search strategies for finding new thermoelectric compositions based on first principles electronic structure and transport calculations. We illustrate them by application to a search for potential n-type oxide…
Polycrystalline LiMnBO3 is a promising cathode material for Li-ion batteries. In this work, we investigated the thermal, structural and electrical properties of glassy and nanocrystallized materials having the same chemical composition. The…
We introduce an open-source, fully atomistic second-principles interatomic potential for lead titanate (PbTiO3), a benchmark ferroelectric material known for its strong polarization and hightemperature phase transitions. While density…