Related papers: Quantum simulation of 3He impurities and of 4He in…
The macroscopic behavior of polycrystalline materials is influenced by the local variation of properties caused by the presence of impurities and defects. The effect of these impurities at the atomic scale can either embrittle or strengthen…
Recent experimental realization of strongly imbalanced mixtures of ultracold atoms opens new possibilities for studying impurity dynamics in a controlled setting. We discuss how the techniques of atomic physics can be used to explore new…
We consider an impurity in a sea of zero-temperature fermions uniformly distributed throughout the space. The impurity scatters on fermions. On average, the momentum of impurity decreases with time as $t^{-1/(d+1)}$ in $d$ dimensions, and…
We made heat-capacity measurements of two dimensional (2D) $^3$He adsorbed on graphite preplated with monolayer $^4$He in a wide temperature range (0.1 $\leq T \leq$ 80 mK) at densities higher than that for the 4/7 phase (= 6.8 nm$^{-2}$).…
An analytical solution of the equations describing impurity diffusion due to the migration of nonequilibrium impurity interstitial atoms was obtained for the case of the Robin boundary condition on the surface of a semiconductor. The…
Symmetry, dimensionality, and interaction are crucial ingredients for phase transitions and quantum states of matter. As a prominent example, the integer quantum Hall effect (QHE) represents a topological phase generally regarded as…
Superfluid phases of 3He are quantuim liquids with the interacting fermionic and bosonic fields. In many respects they can simulate the interacting quantum fields in the phyiscal vacuum. One can observe analogs of such phenomena as axial…
This paper discusses the influence of the channel impurity distribution on the transport and the drive current in short-gate MOSFET. In this purpose, a careful description of electron-ion interaction suitable for the case of discrete…
We propose a simple idea to construct 1D integrable models with impurities. We illustrate the strategy for a supersymmetric $t-J$ Hamiltonian in considerable detail. The impurity comprises the local deformation of the hopping and exchange…
Within density functional theory, we have obtained the structure of $^4$He droplets doped with neutral calcium atoms. These results have been used, in conjunction with newly determined {\it ab-initio} $^1\Sigma$ and $^1\Pi$ Ca-He pair…
The gapless fermionic excitations in superfluid 3He-A have the "relativistic" spectrum close to the gap nodes. This allowed us to model the modern cosmological scenaria of baryogenesis and magnetogenesis. The same massless fermions induce…
We study systems of multiple interacting quantum impurities deposited on a metallic surface in a 3D host. For the real-space two-impurity problem, using numerical renormalization group calculations, a rich range of behavior is shown to…
Solid 4He has been created off the melting curve by growth at nearly constant mass via the "blocked capillary" technique and growth from the 4He superfluid at constant temperature. The experimental apparatus allows injection of 4He atoms…
Low temperature structural and superfluid properties of $^4$He confined in cylindrical nanopores are theoretically investigated by means of first principle Quantum Monte Carlo (QMC) simulations. We vary the density of $^4$He inside the…
In materials with strong local Coulomb interactions, simple defects such as atomic substitutions strongly affect both macroscopic and local properties of the system. A nonmagnetic impurity, for instance, is seen to induce magnetism nearby.…
We discuss effects of various impurities on the magnetic susceptibility and the specific heat of the quantum S=1/2 Heisenberg antiferromagnet on a two-dimensional square lattice. For impurities with spin S_i > 0 (here S_i=1/2 in the case of…
We present a theoretical framework to describe the integer quantum Hall effect (IQHE) in three-dimensional (3D) electron systems. This extends our previous single-electron approach, which was successfully applied to two-dimensional (2D)…
We study the electronic structure of a spherical jellium in the presence of a central Gaussian impurity. We test how well the resulting inhomogeneity effects beyond spherical jellium are reproduced by several approximations of density…
Motivated by recent experiments, we investigate a single $^{133}\text{Cs}$ impurity in the center of a trapped $^{87}\text{Rb}$ Bose-Einstein condensate. Within a zero-temperature mean-field description we provide a one-dimensional physical…
We present a thermodynamic description of a single magnetic impurity at the edge of a superconducting wire. The impurity exhibits four phases $\unicode{x2014}$ Kondo, Yu-Shiba-Rusinov (YSR) I and II, and local moment $\unicode{x2014}$ a…