Effect of alloying elements (Zr, Hf, Co), heat and mechanical treatment conditions on the phase composition and magnetic properties of SmFe11Ti compounds with ThMn12 structure

The results of thermomagnetic, metallographic and X-ray diffraction phase analysis as well as the measurements of specific magnetization (σs), Curie temperature (TC), coercive force (HC) of (Sm,M)(Fe,M)12-xTix alloys samples, where M = Zr, Hf, Co with the ThMn12 main phase structure (1-12) are presented. The effect of the annealing temperature and the cooling rate on the formation of 1-12 phase and its magnetic properties, including the effect of high-energy milling on the magnetic hysteresis properties and alloys structure are described. It was found that the highest magnetic characteristics such as σs = 112.6 emu/g and TC = 600°C are attained in the (Sm0.8Zr0.2)(Fe0.75Co0.25)11.4Ti0.6 alloy after its annealing at 1050 °C and rapid cooling. It is noted that a mechanical milling of the alloy leads to 1-12 phase amorphization which accompanied by an α-(Fe) or metal Co phases impurity formation. © 2018 The Authors, published by EDP Sciences.The work was supported by the State contracts No. 3.6121.2017/ 8.9 between UrFU and the Ministry of Education and Science of Russian Federation and by the Fund of assistance to development of small enterprises in scientific-technical sphere No. 11996GU / 017

Quadrupolar contact terms and Hyperfine Structure

In the interaction of two electric quadrupoles, there is at short distances a contact term proportional to the second derivative of a delta function. This contact term contributes to the hyperfine splitting of bound states of two particles with spin one or higher-for example the bound states of Omega minus and a nucleus of spin one.The contact hyperfine splitting occurs in states with orbital angular momentum one(p-wave), in contrast to the Fermi contact interaction which is in s-states.We find that these contact splittings will be observable with Omega minus atoms and help measure the quadrupole moment and charge radius of the hyperon.Comment: 19 pages; two sentences deleted from first versio

Time Reversal Invariance Violating and Parity Conserving effects in Neutron Deuteron Scattering

Time reversal invariance violating parity conserving effects for low energy elastic neutron deuteron scattering are calculated for meson exchange and EFT-type of potentials in a Distorted Wave Born Approximation, using realistic hadronic wave functions, obtained by solving three-body Faddeev equations in configuration space.Comment: There was a technical mistake in calculations due to singular behavior of Yukawa functions at short range. We corrected the integration algorithm. There were some typos which are corrected. arXiv admin note: text overlap with arXiv:1104.305

Genetics of aging and longevity

Lifespan is a complex quantitative characteristic that makes a significant contribution to the Darwinian adaptiveness. The disclosure of the genetic structure of longevity is a fundamental problem of the evolution of ontogeny, evolutionary genetics and molecular gerontology. Under optimal conditions, the lifespan is determined by the aging rate. The aging process is made up of interrelated processes that take place at the organismal, tissue, cellular, molecular and genetic levels. These include deregulation processes of homeostasis maintenance, metabolic reactions and sending intra- and intercellular signals, accumulation of senescent cells, damaged organelles and macromolecules, epigenetic changes and genetic instability. The objective of this review is to summarize the available information about underlying genetic determinants of longevity and aging. Genes and signaling pathways that regulate stress response, metabolism, growth of cells and organism, maintaining of genome and proteome integrity, qualitative and quantitative mitochondria composition, inflammatory response, apoptosis and selection of viable cells, as well as circadian rhythms were considered. The redistribution of energy resources from one pathway to the other can induce or inhibit the ”longevity program”, providing increased vitality and aging slowdown. Based on the analysis of geroprotective potential of examined genes’ regulation, main targets have been identified to slowdown aging and achieve healthy longevity. These trends include heterochromatin recovery, retrotransposition suppression, aneuploidy elimination; restoring the acidity of lysosomes; telomere elongation; suppression of chronic inflammation; elimination of protein cross-links; elimination of senescent cells; recovery of NAD+ levels; inhibition of mTOR, S6K, TGF-β, AT1; controlled activation of the ”longevity program” genes FOXO, AMPK, PGC1α, NRF2

Improving Josephson junction reproducibility for superconducting quantum circuits: junction area fluctuation

Josephson superconducting qubits and parametric amplifiers are prominent examples of superconducting quantum circuits that have shown rapid progress in recent years. With the growing complexity of such devices, the requirements for reproducibility of their electrical properties across a chip have become stricter. Thus, the critical current $I_c$ variation of the Josephson junction, as the most important electrical parameter, needs to be minimized. Critical current, in turn, is related to normal-state resistance the Ambegaokar-Baratoff formula, which can be measured at room temperature. Here, we focus on the dominant source of Josephson junction critical current non-uniformity junction area variation. We optimized Josephson junctions fabrication process and demonstrate resistance variation of $9.8-4.4\%$ and $4.8-2.3\%$ across $22{\times}22$ $mm^2$ and $5{\times}10$ $mm^2$ chip areas, respectively. For a wide range of junction areas from $0.008$ ${\mu}m^2$ to $0.12$ ${\mu}m^2$ we ensure a small linewidth standard deviation of $4$ $nm$ measured over 4500 junctions with linear dimensions from $80$ to $680$ $nm$. The developed process was tested on superconducting highly coherent transmon qubits $(T_1 > 100\:{\mu}s)$ and a nonlinear asymmetric inductive element parametric amplifier

Broadband SNAIL parametric amplifier with microstrip impedance transformer

Josephson parametric amplifiers have emerged as a promising platform for quantum information processing and squeezed quantum states generation. Travelling wave and impedance-matched parametric amplifiers provide broad bandwidth for high-fidelity single-shot readout of multiple qubit superconducting circuits. Here, we present a quantum-limited 3-wave-mixing parametric amplifier based on superconducting nonlinear asymmetric inductive elements (SNAILs), whose useful bandwidth is enhanced with an on-chip two-section impedance-matching circuit based on microstrip transmission lines. The amplifier dynamic range is increased using an array of sixty-seven SNAILs with 268 Josephson junctions, forming a nonlinear quarter-wave resonator. Operating in a current-pumped mode, we experimentally demonstrate an average gain of $17 dB$ across $300 MHz$ bandwidth, along with an average saturation power of $- 100 dBm$, which can go as high as $- 97 dBm$ with quantum-limited noise performance. Moreover, the amplifier can be fabricated using a simple technology with just a one e-beam lithography step. Its central frequency is tuned over a several hundred megahertz, which in turn broadens the effective operational bandwidth to around $1.5 GHz$.Comment: 7 pages, 3 figure

HYSTERESIS PROPERTIES AND MAGNETIZATION REVERSAL IN FeMn/FM (FM=Co, Fe, Ni, FeNi) FILMS WITH EXCHANGE BIAS

Angular dependencies of hysteresis properties of various ferromagnetic layers exchange coupled to a pinning antiferromagnetic layer have been investigated experimentally. The re-sults have been interpreted and analyzed in detail using macrospin approximation and micro-magnetic simulation.This work was supported by the Russian Science Foundation (project No 19-72-00141)

Molecular CP-violating magnetic moment

A concept of CP-violating (T,P-odd) permanent molecular magnetic moments $\mu^{CP}$ is introduced. We relate the moments to the electric dipole moment of electron (eEDM) and estimate $\mu^{CP}$ for several diamagnetic polar molecules. The moments exhibit a steep, Z^5, scaling with the nuclear charge Z of the heavier molecular constituent. A measurement of the CP-violating magnetization of a polarized sample of heavy molecules may improve the present limit on eEDM by several orders of magnitude.Comment: 4 pages, no figures, submitted to PR

Investigation of magnetization reversal processes in Sm(Co, Fe, Cu, Zr)7.5 magnets

The processes of magnetization reversal in isotropic and anisotropic commercial permanent magnets Sm(Co, Fe, Cu, Zr)7.5 were investigated. Features of magnetization reversal process in both textured and isotropic magnets were analyzed with δM(H) plots, magnetic susceptibility and initial magnetization curves. The magnetization reversal of Sm(Co, Fe, Cu, Zr)7.5 magnets is more complicated than that described in the coercivity model based on the domain walls pinning. © Published under licence by IOP Publishing Ltd.The work was supported by Act 211 Government of the Russian Federation, contract № 02.A03.21.0006