Probability representation and quantumness tests for qudits and two-mode light states

Using tomographic-probability representation of spin states, quantum behavior of qudits is examined. For a general j-qudit state we propose an explicit formula of quantumness witnetness whose negative average value is incompatible with classical statistical model. Probability representations of quantum and classical (2j+1)-level systems are compared within the framework of quantumness tests. Trough employing Jordan-Schwinger map the method is extended to check quantumness of two-mode light states.Comment: 5 pages, 2 figures, PDFLaTeX, Contribution to the 11th International Conference on Squeezed States and Uncertainty Relations (ICSSUR'09), June 22-26, 2009, Olomouc, Czech Republi

Quantum Fluctuations in Josephson Junction Comparators

We have developed a method for calculation of quantum fluctuation effects, in particular of the uncertainty zone developing at the potential curvature sign inversion, for a damped harmonic oscillator with arbitrary time dependence of frequency and for arbitrary temperature, within the Caldeira-Leggett model. The method has been applied to the calculation of the gray zone width Delta Ix of Josephson-junction balanced comparators driven by a specially designed low-impedance RSFQ circuit. The calculated temperature dependence of Delta Ix in the range 1.5 to 4.2K is in a virtually perfect agreement with experimental data for Nb-trilayer comparators with critical current densities of 1.0 and 5.5 kA/cm^2, without any fitting parameters.Comment: 4 pages, 4 figures, submitted to Physical Review Letter

Distances between quantum states in the tomographic-probability representation

Distances between quantum states are reviewed within the framework of the tomographic-probability representation. Tomographic approach is based on observed probabilities and is straightforward for data processing. Different states are distinguished by comparing corresponding probability-distribution functions. Fidelity as well as other distance measures are expressed in terms of tomograms.Comment: 10 pages, Contribution to the 16th Central European Workshop on Quantum Optics (CEWQO'09), May 23-27, 2009, Turku, Finlan

Manipulations of individual molecules by scanning probe microscopy

In this Letter we suggest a new method of manipulating individual molecules with scanning probes using a "pick-up-and put-down" mode. We demonstrate that the number of molecules picked up by the tip and deposited in a different location can be controlled by adjusting the pulling velocity of the tip and the distance of closest approach of the tip to the surface

Influence of Alzheimer's β-amyloid peptide on the lateral diffusion of lipids in raft-forming bilayers

The effect of added Alzheimer's Aβ(1-40) peptide of the wild type on the lateral diffusion of lipids in macroscopically oriented bilayers of 'raft' compositions [a mixture of dioleoylphosphatidylcholine (DOPC), sphingomyelin (SM) and cholesterol (CHOL)] was studied by an NMR-diffusion technique. In homogeneous bilayers, diffusion coefficients decrease, while they change differently in liquid ordered and in liquid disordered phases at varied concentrations of CHOL; this was explained by the decreased maximum solubility of CHOL in phospholipids in the presence of Aβ(1-40) peptide. © 2013 Mendeleev Communications. All rights reserved

Estimating the cutting force when skiving with a radius cutter

The paper considers the method of determining the components of the cutting force under cutting completed with a radius cutter. The authors provide the design of the experimental study. The authors provide the data on the cutting force change in the process of turning with a radius cutter according to the cutting edge inclination, cutting depth and supply obtained experimentally and calculated analytically. The paper also provides the results of experimental work approximation and theoretical error checking related to experimental data

Static magnetic field alters properties of confined alkylammonium nitrate ionic liquids

© 2018 Elsevier B.V. Ethylammonium nitrate (EAN) and propylammonium nitrate (PAN) ionic liquids confined between polar glass plates and exposed to a strong magnetic field of 9.4 T demonstrate gradually slowing diffusivity, a process that can be reversed by removing the sample from the magnetic field. The process can be described well by the Avrami equation, which is typical for autocatalytic (particularly, nucleation controlled) processes. The transition can be stopped by freezing the sample. Cooling and heating investigations showed differences in the freezing and melting behavior of the sample depending on whether it had been exposed to the magnetic field. After exposure to the magnetic field, the sample demonstrated decrease in the 1H NMR signal of residual water. 1H NMR spectroscopy with presaturation demonstrates that the most probable mechanism of the decrease of the bulk water signal is adsorption of water on polar surfaces of glass plates. Generally, our findings confirm our previous suggestion that alteration of the dynamic properties of confined alkylammonium nitrate ionic liquids exposed to a magnetic field is related to the alteration of real physical-chemical phases

Interatomic interaction at the aluminum-fullerene C60\mathrm{C}_{60} interface

We propose a model describing the interatomic interaction at the interface between fullerene $\mathrm{C}_{60}$ and aluminum. Using the density functional theory, we calculate the binding energy and the fullerene's position on the $\mathrm{Al}(111)$ slab. The obtained data are applied to estimate the parameters of the Lennard-Jones potential for carbon and aluminum atoms, which is then used in molecular dynamics simulations. The results of the theoretical study of desorption of fullerenes from an aluminum substrate are in good agreement with those of the experiments from the literature. We also investigate the capillary effects in an aluminum melt with submerged fullerenes. The positive interface surface energy indicates the poor wettability of $\mathrm{C}_{60}$ by the melt. The calculated value of the diffusion relaxation time is approximately two orders of magnitude less than the characteristic coagulation time of fullerenes. The activation character of the coagulation process and the capillary nature of the interaction between fullerenes are discussed.Comment: 15 pages, 9 figure