Transformation of quantum correlations between systems of different physical nature

Using the general equation for two independent two-level atoms in a broadband two-component entangled bath, the problem of transforming quantum correlations from light to atoms is considered. To identify the transfer of inseparability, it is proposed to choose an adequate observable. Finally, we consider the average fidelity, which is a characteristic of the channel in the teleportation process.     

Tuning the morphology and magnetic properties of single-domain SrFe8Al4O19 particles prepared by a citrate auto-combustion method

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Bernstein Inequality in $$L^p$$ on the Line with Power Weight for $$p>0$$

Mathematical Notes -     

Relaxation in an entangled thermostat

A generalized Lindblad equation is derived that describes the relaxation of two systems of an arbitrary physical nature in an entangled thermostat. The relaxation of an atom and a mode of the electromagnetic field selected by a high-Q cavity is considered as an example. Using the introduced collective operators for an atom and a mode, it is shown that the entangled state of the thermostat can lead to the coherent and squeezed state of the atom and the mode.     

Novel microwave plasma‐assisted CVD reactor for diamond delta doping

We report on building a novel chemical vapor deposition (CVD) reactor for diamond delta‐doping. The main features of our reactor are: a) the use of rapid gas switching system, (b) the reactor design providing the laminar gas flow. These features provide the creation of ultra‐sharp interfaces between doped and undoped material and minimize the prolonged ”tails” formation in the doping profile. It is proved by optical emission spectroscopy that gas switching time is not more than 10 seconds. Using the novel reactor we have grown the nanometer‐thin layers of boron doped diamond. The FWHM of boron concentration profile is about 2 nm which is proved by SIMS. It is shown that the both single delta‐layer and multiple delta‐layers could be grown using the novel CVD reactor. In principle, the reactor could be used for diamond delta doping with other dopants, like nitrogen, phosphorus etc. (© 2016 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)     

Weak localization in bilayer graphene

We have performed the first experimental investigation of quantum interference corrections to the conductivity of a bilayer graphene structure. A negative magnetoresistance--a signature of weak localization--is observed at different carrier densities, including the electroneutrality region. It is very different, however, from the weak localization in conventional two-dimensional systems. We show that it is controlled not only by the dephasing time, but also by different elastic processes that break the effective time-reversal symmetry and provide intervalley scattering.     

Relationship between the kinetics of transformations with linear temperature programming and the kinetics of transformations with exponential and hyperbolic temperature programming

An analytical relationship between the kinetics of non-isothermal transformations with linear, exponential and hyperbolic temperature programming is demonstrated.     

Entangled states of atoms upon interaction with narrowband light

The process of resonant interaction of light with two-level atoms in the absence of relaxation is considered. For a special form of initial conditions, simple and exact solutions are found that describe coherent processes leading to the appearance of many-particle entangled W-class states. These processes can be used for preparation and transformation of entangled states, in particular, for problems of quantum memory and generation of entangled atomic chains.     

A powerful source of entangled states of light

The simultaneous interaction of N two-level atoms with a quasi-resonant classical field and two quantized modes is considered under the assumption that the Rabi parameter of the classical mode substantially exceeds the effective Rabi parameters of the quantized modes. It is shown that, in a certain domain of the parameters, the population of the quantized modes exponentially depends on time and the number N. At certain instants of time, the states of the quantized modes prove to be close to the totally entangled state.     

Evolution of fractal particles in systems with conserved order parameter

Computer simulations of the evolution of fractal aggregates in systems with conserved order parameter are described in this work. The aggregates are generated by diffusion-limited aggregation. This model describes such important processes as annealing of dendrite inclusions in solids, healing of cracks in ceramics, temperature-induced transformations in composites, relaxation of rough surfaces, aging of colloid particles, etc. It is shown that the evolution in fractal media differs significantly from that occurring in initially homogeneous systems and leads to different values of the scaling exponent. A relationship between the fractal dimension, mechanism of relaxation, and scaling exponent was also derived.