Nonlinear Screening and the Metal–Insulator Transition in a Two-Dimensional Electron Gas

Russian Physics Journal - The density functional theory is used to study the nonlinear screening properties of a two-dimensional electron gas in a strong magnetic field. The Kohn-Sham equations for...     

Metal–Insulator Phase Transition in Thin Films of a Nickel-Doped Vanadium Dioxide

Physics of the Solid State - The electrical conductivity of thin polycrystalline VNixO2 films has been studied in a wide range of temperatures, which covers the regions of both metallic and...     

Probing a Dissipative Phase Transition with a Trapped Ion through Reservoir Engineering

Dissipation is often considered as a detrimental effect in quantum systems for unitary quantum operations.However, it has been shown that suitable dissipation can be useful resources in both quantum information and quantum simulation. Here, we propose and experimentally simulate a dissipative phase transition(DPT) model using a single trapped ion with an engineered reservoir. We show that the ion’s spatial oscillation mode reaches a steady state after the alternating application of unitary evolu...     

Electronic Properties of a Two-Dimensional Electron Gas at the Interface between Transition Metal Complex Oxides

The structural and electronic properties of heterostructures based on transition metal oxides containing strongly correlated electrons are compared. The investigated structures are LaAlO₃/SrTiO₃ (LAO/STO), LaAlO₃/BaTiO₃ (LAO/BTO), and BaTiO₃/SrTiO₃ (BTO/STO). The role of structural relaxation in the formation of a two-dimensional electron gas at the interface of two dielectrics is revealed. The contribution from different orbitals and atoms to conductivity is analyzed, along with the correlation between structural distortions induced by the dipole moment in an LAO layer and conductivity.     

A Two-Parameter Model for the Metal–Semiconductor Phase Transition in a One-Dimensional Atomic System

A model is developed for a metal–semiconductor phase transition and a concurrent structural phase transformation in a one-dimensional system of atoms, each having one external electron. The interatomic interaction involves two components. One component is associated with atom shells, while another (of covalent nature) is due to overlap of the electron wave functions of neighboring atoms. It is found experimentally that the phase transition gives rise to the formation of a band gap in the electron spectrum and to the development of static phonon modes. These effects are accounted for by the numerical model under review. The results obtained are used to interpret the experimental data on the metal–semiconductor phase transition in VO₂.