相关论文: Structural instability of the ground state of the …

In order to improve the hydrogen storage properties of calcium hydride (CaH2), we have tuned its thermodynamical properties through fluorination. Using ab-initio total energy calculations based on density functional theory, the structural…

Single crystals of EuPd2Sb2 have been grown from PdSb self-flux. The properties of the single crystals have been investigated by x-ray diffraction, magnetic susceptibility chi, magnetization M, electrical resistivity rho, Hall coefficient…

We study the superconducting instability of a two-dimensional disordered Fermi liquid weakly coupled to the soft fluctuations associated with proximity to an Ising-ferromagnetic quantum critical point. We derive interaction-induced…

Iron oxide is a key compound to understand the state of the deep Earth. It has been believed that previously known oxides such as FeO and Fe2O3 will be dominant at the mantle conditions. However, recent observation of FeO2 shed another…

Multiplicity of phase states within frequency locked bands in periodically forced oscillatory systems may give rise to front structures separating states with different phases. A new front instability is found within bands where…

Motivated by recently reported experimental phase diagrams, we study the effects of CoO6 distortion on the electronic structure in NaxCoO2.yH2O. We construct the multiband tight-binding model by employing the LDA result. Analyzing this…

We study the charge-density wave phase in $\textup{TiSe}_2$ by using first principle calculations. We show that, regardless of the local functional used and as long as the cell parameters are in agreement with the experiment,…

The temperature-induced orthorhombic to cubic phase transition in Li2C2 is a prototypical example of a solid to solid phase transformation between an ordered phase, which is well described within the phonon theory, and a dynamically…

We show that 2D and 3D electron systems with the long-range Coulomb electron-electron interaction could develop ferromagnetic instabilities due to strong exchange effects at low densities. The critical densities in both 2D and 3D systems at…

We used first-principles calculations to investigate the existence and origin of the ferroelectric in- stability in the ABF3 fluoro-perovskites. We find that many fluoro-perovskites have a ferroelectric instability in their high symmetry…

Cation disorder is an important design criterion for technologically relevant transition-metal (TM) oxides, such as radiation-tolerant ceramics and Li-ion battery electrodes. In this letter, we use a combination of first-principles…

A complete mapping in the Brillouin zone of the structural instability associated with the ferroelectric phase transitions of KNbO$_3$ has been obtained by first-principles calculations using an LAPW linear response approach. The wavevector…

In the recently discovered Co-oxide superconductor Na_xCoO_2*yH_2O, the edge-shared CoO6 octahedra are trigonally contracted along the c-axis in the CoO2-plane. We study how this CoO6 distortion affects the magnetic properties and…

The micro-bunching instability is a longitudinal instability that leads to dynamical deformations of the charge distribution in the longitudinal phase space. It affects the longitudinal charge distribution, and thus the emitted coherent…

We theoretically investigate the dynamics of modulation instability (MI) in two-dimensional spin-orbit coupled Bose-Einstein condensates (BECs). The analysis is performed for equal densities of pseudo-spin components. Different combination…

We investigate the $2k_F$ density-wave instability of non-Fermi liquid states by combining exact diagonalization with renormalization group analysis. At the half-filled zeroth Landau level, we study the fate of the composite Fermi liquid in…

In this work, electronic structure of several doped TiO$_2$ anatase systems is computed using DFT+$U$. Effective masses of charge carriers are also computed to quantify how the dopant atoms perturb the bands of the host anatase material.…

We consider a BEC of rigid rotor molecules confined to quasi-2d through harmonic trapping. The molecules are subjected to an external electric field which polarizes the gas, and the molecules interact via dipole-dipole interactions. We…

Pb$_2$CoOsO$_6$ is a newly synthesized polar metal in which inversion symmetry is broken by the magnetic frustration in an antiferromagnetic ordering of Co and Os sublattices. The coupled magnetic and structural transition occurs at 45 K at…

We discuss models of the modulational instability in a cold exciton system in coupled quantum wells. One mechanism involves exciton formation in a photoexcited electron-hole system in the presence of stimulated binding processes which build…