相关论文: Potential of an ionic impurityin a large $^4$He cl…
Non-linear theory of diffusion of impurities in porous materials upon ultrasonic treatment is described. It is shown that at a defined value of deformation amplitude, an average concentration of vacancies and temperature as a result of the…
Recent observations have revealed that the ion-neutral drift velocity in star-forming molecular clouds and dense cores is on the order of 100 m s^-1. Theoretical studies have shown that, in ambipolar diffusion, the process responsible for…
We actively stabilize the harmonic oscillation frequency of a laser-cooled atomic ion confined in a rf Paul trap by sampling and rectifying the high voltage rf applied to the trap electrodes. We are able to stabilize the 1 MHz atomic…
We study the influence of micromotion on the spectrum of trapped ions with a lambda-type level scheme, leading to dark resonances due to coherent population trapping. We work with calcium ions trapped in a ring-shaped Paul trap, in which…
Gold clusters Aun of size n = 2 to 12 atoms were studied by the density-functional theory with an ab-initio pseudopotential and a generalized gradient approximation. Geometry optimizations starting from a number of initial candidate…
Extending earlier work on a vibronic theory of the FA centers in alkali halides, the reorientation is now considered of an off-center Li+ impurity, either isolated or near an F center. We derive analytically periodic potential energy…
We consider an impurity in a semi-infinite one-dimensional system of weakly-interacting bosons. We calculate the interaction potential for the impurity due to the end of the system, i.e., the wall. For local repulsive (attractive)…
We suggested a theory of clustering of inertial particles advected by a turbulent velocity field caused by an instability of their spatial distribution. The reason of the {\em clustering instability} is a combined effect of the particle…
Transport, separation, and merging of trapped ion crystals are essential operations for most large-scale quantum computing architectures. In this work, we develop a theoretical framework that describes the dynamics of ions in time-varying…
Marked velocity excesses of ions relative to neutrals are obtained from two time series of the neighboring emission lines He I 5015 and Fe II 5018 in a quiescent prominence. Their Doppler shifts show time variations of quasi-periodic…
For experiments with ions confined in a Paul trap, minimization of micromotion is often essential. In order to diagnose and compensate micromotion we have implemented a method that allows for finding the position of the radio-frequency (RF)…
The interaction of ionizing radiation with nanometric targets is a field of interest for many branches of science such as: radiology, oncology, radiation protection and nanoelectronics. A new experimental technique known as nanodosimetry…
Ab initio calculations have been performed to clarify the primary behaviors of He atoms in vanadium and to generate the database for the development of the interatomic potential for V-He system within the framework of the"s-band"model.The…
We study the renormalization of a single impurity potential in one-dimensional interacting electron systems in the presence of magnetic field. Using the bosonization technique and Bethe ansatz solutions, we determine the renormalization…
The drift wave in the presence of impurity ions was investigated numerically in reversed field pinch (RFP) plasmas, using the gyrokinetic integral eigenmode equation. It was found that in RFP plasmas with hollow density profiles, an…
We show that ion masses in superfluid $^3$He ought to be enormously enhanced (by a factor of 100) as compared with the same ion masses in $^4$He measured at low temperature. We calculate precisely the dependence of the effective mass on…
We study the problem of an impurity in fully polarized (spin-up) low density neutron matter with the help of an accurate quantum Monte Carlo method in conjunction with a realistic nucleon-nucleon interaction derived from chiral effective…
We consider a bilayer geometry where a single impurity moves in a two-dimensional plane and is coupled, via dipolar interactions, to a two-dimensional system of fermions residing in the second layer. Dipoles in both layers point in the same…
We present a numerical analysis of spin-$\frac{1}{2}$ fermions in a one-dimensional harmonic potential in the presence of a magnetic point-like impurity at the center of the trap. The model represents a few-body analogue of a magnetic…
We proposed the non-perturbative scheme for calculation of the impurity spectrum in the Bose system at zero temperature. The method is based on the path-integral formulation and describes an impurity as a zero-density ideal Fermi gas…