238 citations · 1k across the 15 of their papers we have counts for
15 papers
Phonon anharmonicity: a pertinent review of recent progress and perspective
Bin Wei, Qiyang Sun, Chen Li +1
Anharmonic lattice vibrations govern the thermal dynamics in materials and present how the atoms interact and how they conduct heat. An indepth understanding of the microscopic mec…
Giant Anisotropic in-Plane Thermal Conduction Induced by Anomalous Phonons in Nearly-Equilaterally Structured PdSe2
Bin Wei, Junyan Liu, Qingan Cai +4
In two-dimensional materials, structure difference induces the difference in phonon dispersions, leading to the anisotropy of in-plane thermal transport. Here, we report an excepti…
Matryoshka Phonon Twinning in alpha-GaN
Bin Wei, Qingan Cai, Qiyang Sun +5
Understanding lattice dynamics is crucial for effective thermal management in high-power electronic devices because phonons dominate thermal transport in most semiconductors. This…
Screening piezoelectricity in determination of flexoelectric coefficient at nanoscale
Yingzhuo Lun, Hao Zhou, Di Yao +2
Piezoelectricity usually accompanies with flexoelectricity in polar materials which is the linear response of polarization to a strain gradient. Therefore, it is hard to eliminate…
Phonon anharmonicity and negative thermal expansion in SnSe
Dipanshu Bansal, Jiawang Hong, Chen W. Li +5
The anharmonic phonon properties of SnSe in the Pnma phase were investigated with a combination of experiments and first-principles simulations. Using inelastic neutron scattering…
Electronic Instability and Anharmonicity in SnSe
Jiawang Hong, Olivier Delaire
The binary compound SnSe exhibits record high thermoelectric performance, largely because of its very low thermal conductivity. The origin of the strong phonon anharmonicity leadin…
Analytical method to determine flexoelectric coupling coefficient at nanoscale
Hao Zhou, Yongmao Pei, Jiawang Hong +1
Flexoelectricity is defined as the coupling between strain gradient and polarization, which is expected to be remarkable at nanoscale. However, measuring the flexoelectricity at na…
First-principles theory and calculation of flexoelectricity
Jiawang Hong, David Vanderbilt
We develop a general and unified first-principles theory of piezoelectric and flexoelectric tensor, formulated in such a way that the tensor elements can be computed directly in th…
Electrically driven octahedral rotations in SrTiO3 and PbTiO3
Jiawang Hong, David Vanderbilt
We investigate the oxygen octahedral rotations that occur in two perovskites, SrTiO3 and PbTiO3, as a function of applied three-dimensional electric displacement field, allowing us…
External uniform electric field removing flexoelectric effect in epitaxial ferroelectric thin films
Hao Zhou, Jiawang Hong, Yihui Zhang +3
Using the modified Landau-Ginsburg-Devonshire thermodynamic theory, it is found that the coupling between stress gradient and polarization, or flexoelectricity, has significant eff…
Flexoelectricity induced increase of critical thickness in epitaxial ferroelectric thin films
Hao Zhou, Jiawang Hong, Yihui Zhang +3
Flexoelectricity describes the coupling between polarization and strain/stress gradients in insulating crystals. In this paper, using the Landau-Ginsburg-Devonshire phenomenologica…
Spin-phonon coupling effects in transition-metal perovskites:a DFT+ and hybrid-functional study
Jiawang Hong, Alessandro Stroppa, Jorge Íñiguez +2
Spin-phonon coupling effects, as reflected in phonon frequency shifts between ferromagnetic (FM) and G-type antiferromagnetic (AFM) configurations in cubic CaMnO, SrMnO, Ba…
First-principles theory of frozen-ion flexoelectricity
Jiawang Hong, David Vanderbilt
We demonstrate that the frozen-ion contribution to the flexoelectric coefficient is given solely in terms of the sum of third moments of the charge density distortions induced by a…
Mapping the energy surface of PbTiO3 in multidimensional electric-displacement space
Jiawang Hong, David Vanderbilt
In recent years, methods have been developed that allow first-principles electronic-structure calculations to be carried out under conditions of fixed electric field. For some purp…
Topology of the polarization field in ferroelectric nanowires from first principles
J. W. Hong, G. Catalan, D. N. Fang +2
The behaviour of the cross-sectional polarization field is explored for thin nanowires of barium titanate from first-principles calculations. Topological defects of different windi…