Generating Many Majorana Modes via Periodic Driving: A Superconductor Model

Realizing Majorana modes (MMs) in condensed-matter systems is of vast experimental and theoretical interests, and some signatures of MMs have been measured already. To facilitate future experimental observations and to explore further applications of MMs, generating many MMs at ease in an experimentally accessible manner has become one important issue. This task is achieved here in a one-dimensional $p$-wave superconductor system with the nearest- and next-nearest-neighbor interactions. In particular, a periodic modulation of some system parameters can induce an effective long-range interaction (as suggested by the Baker-Campbell-Hausdorff formula) and may recover time-reversal symmetry already broken in undriven cases. By exploiting these two independent mechanisms at once we have established a general method in generating many Floquet MMs via periodic driving.Comment: 5 pages, 3 figures. To appear in Phys. Rev. B as a Rapid Communicatio

Next-to-Leading Order Corrections to Single Top Quark Production and Decay at the Tevatron: 1. s-channel Process

We present a study of s-channel single top quark production at the upgraded Tevatron $p\bar{p}$ collider, including the next-to-leading order (NLO) QCD corrections to the production and the decay of the top quark. The "modified" narrow width approximation was adopted to preserve the spin of the top quark in its production and decay. We discuss the effect of the different $O(\alpha_s)$ contributions on the inclusive cross section as well as various kinematic distributions after imposing the relevant cuts to select s-channel single top signal events. In particular the $O(\alpha_s)$ decay contribution, while small in size, has a significant impact on several distributions. With the help of the best-jet algorithm to reconstruct the top quark we demonstrate that it is possible to study kinematical and spin correlations in s-channel single top events. We furthermore compare top quark spin measurements in two different basis and show how NLO corrections have to be taken into consideration in searches for the Higgs boson through $W^{\pm}H$ associated production at the Tevatron.Comment: 39 pages, 37 figure

Single Top Quark Production and Decay at Next-to-leading Order in Hadron Collision

We present a calculation of the next-to-leading order QCD corrections, with one-scale phase space slicing method, to single top quark production and decay process $p\bar{p},pp\to t\bar{b}+X\to b\ell\nu\bar{b}+X$ at hadron colliders. Using the helicity amplitude method, the angular correlation of the final state partons and the spin correlation of the top quark are preserved. The effect of the top quark width is also examined.Comment: 47 pages, 9 figure

Study on Salting Out-Steam Distillation Extraction Technology and Antibacterial Activities of Essential Oil From Cumin Seeds

The effects of different factors on the yield of essential oil from were discussed, and the extraction conditions of essential oil from cumin seeds by salting out-steam distillation technology based on single-factor test and orthogonal experiment, as well as its antibacterial activities on several common food spoilage bacteria were studied in this paper. The results showed that, the impact order of the influence factors was liquid/solid ratio > distilling time > NaCl concentration, and optimized extraction conditions were as follows, liquid to material ratio 15:1, soaking time 1 h, 4% NaCl, steam distilling time 3 h. The yield of essential oil was up to 4.48% under these conditions. The results of antibacterial activity assays showed that the essential oil from cumin seeds exhibited the different antibacterial activities against some food borne pathogens, especially it presented the best inhibitory effect against Bacillus subtilis with the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of 6.25 and 12.5 mg/mL respectively, followed by Staphylococcus albus and Staphylococcus aureus, the lowest for Pseudomonas aeruginosa and Shigella dysenteria

Effect of infiltration time on the microstructure and mechanical properties of C/C-SiC composite prepared by Si‐Zr10 alloyed melt infiltration

Low cost C/C-SiC composites were prepared through reactive melt infiltration with Si-Zr10 alloy infiltrant under different infiltration time. Effect of infiltration time on the microstructure and mechanical properties of the composite were investigated. ZrC tended to be formed in the composite and the amount of carbon phase decreased with an extension in the infiltration time according to the X-ray diffraction results. Phase transformation of the C/C-SiC composite was analyzed based on C-Si-Zr phase diagram. Flexural strength of the composite prepared by preform 0.9 g/cm³ decreased with an increase in the infiltration time while that of the composite prepared by preform 1.38 g/cm³ increased initially and then decreased reversely. The highest flexural strength of the composite was found at about 324 MPa. Flexural strength of the composite is considered to depend on its phase composition and fiber-matrix interface.This work was supported by National Natural Science Foundation of China (51302315), Innovation Foundation for Excellent Postgraduate of National University of Defense Technology and Hunan Provincial Innovation Foundation for Postgraduate. Yonggang Tong also thanks the support from China Scholarship Council

Effect of gauge boson mass on the phase structure of QED3_{3}

Dynamical chiral symmetry breaking (DCSB) in QED$_{3}$ with finite gauge boson mass is studied in the framework of the rainbow approximation of Dyson-Schwinger equations. By adopting a simple gauge boson propagator ansatz at finite temperature, we first numerically solve the Dyson-Schwinger equation for the fermion self-energy to determine the chiral phase diagram of QED$_3$ with finite gauge boson mass at finite chemical potential and finite temperature, then we study the effect of the finite gauge mass on the phase diagram of QED$_3$. It is found that the gauge boson mass $m_{a}$ suppresses the occurrence of DCSB. The area of the region in the chiral phase diagram corresponding to DCSB phase decreases as the gauge boson mass $m_{a}$ increases. In particular, chiral symmetry gets restored when $m_{a}$ is above a certain critical value. In this paper, we use DCSB to describe the antiferromagnetic order and use the gauge boson mass to describe the superconducting order. Our results give qualitatively a physical picture on the competition and coexistence between antiferromagnetic order and superconducting orders in high temperature cuprate superconductors.Comment: 10 pages, 2 figure

Testing the Bell Inequality at Experiments of High Energy Physics

Besides using the laser beam, it is very tempting to directly testify the Bell inequality at high energy experiments where the spin correlation is exactly what the original Bell inequality investigates. In this work, we follow the proposal raised in literature and use the successive decays $J/\psi\to\gamma\eta_c\to \Lambda\bar\Lambda\to p\pi^-\bar p\pi^+$ to testify the Bell inequality. Our goal is twofold, namely, we first make a Monte-Carlo simulation of the processes based on the quantum field theory (QFT). Since the underlying theory is QFT, it implies that we pre-admit the validity of quantum picture. Even though the QFT is true, we need to find how big the database should be, so that we can clearly show deviations of the correlation from the Bell inequality determined by the local hidden variable theory. There have been some critiques on the proposed method, so in the second part, we suggest some improvements which may help to remedy the ambiguities indicated by the critiques. It may be realized at an updated facility of high energy physics, such as BES III.Comment: 16 pages, 5 figure

Phosphate Rock Application on Alfalfa (Medicago Sativa L.) Production and Macronutrients in Latosol Soil

The objective of this study was to evaluate the effectiveness of phosphate rocks (PRs) fertilizercompared to chemical P fertilizer for the best crop production and macronutrients of alfalfa. Acompletely randomized design under 3x3 factorial patterns was used in this research. The first factorwas different sources of P fertilizer: Guizhou Phosphate Rock (GPR), Jingxiang Phosphate Rock (JPR),and Single Super Phosphate (SSP). The second factor was level of P fertilizer: 75, 100, and 125 mgP2O5/kg soil. A control treatment (without addition of P fertilizer, CK) was added as a comparison withthe treatments. The results showed that JPR was the best for alfalfa production, whereas GPR and SSPwere better for nutrient content in the alfalfa tissue than JPR. On the whole, phosphate rocks had similareffect on alfalfa growth compared to SSP at the experimental conditions