Fe-doping induced superconductivity in charge-density-wave system 1T-TaS2

We report the interplay between charge-density-wave (CDW) and superconductivity of 1$T$-Fe$_{x}$Ta$_{1-x}$S$_{2}$ ($0\leq x \leq 0.05$) single crystals. The CDW order is gradually suppressed by Fe-doping, accompanied by the disappearance of pseudogap/Mott-gap as shown by the density functional theory (DFT) calculations. The superconducting state develops at low temperatures within the CDW state for the samples with the moderate doping levels. The superconductivity strongly depends on $x$ within a narrow range, and the maximum superconducting transition temperature is 2.8 K as $x=0.02$. We propose that the induced superconductivity and CDW phases are separated in real space. For high doping level ($x>0.04$), the Anderson localization (AL) state appears, resulting in a large increase of resistivity. We present a complete electronic phase diagram of 1$T$-Fe$_{x}$Ta$_{1-x}$S$_{2}$ system that shows a dome-like $T_{c}(x)$

Revealing common artifacts due to ferromagnetic inclusions in highly-oriented pyrolytic graphite

We report on an extensive investigation to figure out the origin of room-temperature ferromagnetism that is commonly observed by SQUID magnetometry in highly-oriented pyrolytic graphite (HOPG). Electron backscattering and X-ray microanalysis revealed the presence of micron-size magnetic clusters (predominantly Fe) that are rare and would be difficult to detect without careful search in a scanning electron microscope in the backscattering mode. The clusters pin to crystal boundaries and their quantities match the amplitude of typical ferromagnetic signals. No ferromagnetic response is detected in samples where we could not find such magnetic inclusions. Our experiments show that the frequently reported ferromagnetism in pristine HOPG is most likely to originate from contamination with Fe-rich inclusions introduced presumably during crystal growth.Comment: 8 pages, 7 figure

Einstein Probe - a small mission to monitor and explore the dynamic X-ray Universe

Einstein Probe is a small mission dedicated to time-domain high-energy astrophysics. Its primary goals are to discover high-energy transients and to monitor variable objects in the $0.5-4~$keV X-rays, at higher sensitivity by one order of magnitude than those of the ones currently in orbit. Its wide-field imaging capability, featuring a large instantaneous field-of-view ($60^\circ \times60^\circ$, $\sim1.1$sr), is achieved by using established technology of micro-pore (MPO) lobster-eye optics, thereby offering unprecedentedly high sensitivity and large Grasp. To complement this powerful monitoring ability, it also carries a narrow-field, sensitive follow-up X-ray telescope based on the same MPO technology to perform follow-up observations of newly-discovered transients. Public transient alerts will be downlinked rapidly, so as to trigger multi-wavelength follow-up observations from the world-wide community. Over three of its 97-minute orbits almost the entire night sky will be sampled, with cadences ranging from 5 to 25 times per day. The scientific objectives of the mission are: to discover otherwise quiescent black holes over all astrophysical mass scales by detecting their rare X-ray transient flares, particularly tidal disruption of stars by massive black holes at galactic centers; to detect and precisely locate the electromagnetic sources of gravitational-wave transients; to carry out systematic surveys of X-ray transients and characterize the variability of X-ray sources. Einstein Probe has been selected as a candidate mission of priority (no further selection needed) in the Space Science Programme of the Chinese Academy of Sciences, aiming for launch around 2020.Comment: accepted to publish in PoS, Proceedings of "Swift: 10 Years of Discovery" (Proceedings of Science; ed. by P. Caraveo, P. D'Avanzo, N. Gehrels and G. Tagliaferri). Minor changes in text, references update

Calculations of O(p6){\cal O}(p^6) Resonance Coupling Constants in the Scalar Sector of the ENJL Model

We derive the scalar resonance coupling constants of resonance chiral theory from the Extended Nambu Jona-Lasinio model by using heat-kernel expansion.Comment: 7 page

Multifractal analysis of complex networks

Complex networks have recently attracted much attention in diverse areas of science and technology. Many networks such as the WWW and biological networks are known to display spatial heterogeneity which can be characterized by their fractal dimensions. Multifractal analysis is a useful way to systematically describe the spatial heterogeneity of both theoretical and experimental fractal patterns. In this paper, we introduce a new box covering algorithm for multifractal analysis of complex networks. This algorithm is used to calculate the generalized fractal dimensions $D_{q}$ of some theoretical networks, namely scale-free networks, small world networks and random networks, and one kind of real networks, namely protein-protein interaction networks of different species. Our numerical results indicate the existence of multifractality in scale-free networks and protein-protein interaction networks, while the multifractal behavior is not clear-cut for small world networks and random networks. The possible variation of $D_{q}$ due to changes in the parameters of the theoretical network models is also discussed.Comment: 18 pages, 7 figures, 4 table

Quantum Entanglement and Teleportation in Higher Dimensional Black Hole Spacetimes

We study the properties of quantum entanglement and teleportation in the background of stationary and rotating curved space-times with extra dimensions. We show that a maximally entangled Bell state in an inertial frame becomes less entangled in curved space due to the well-known Hawking-Unruh effect. The degree of entanglement is found to be degraded with increasing the extra dimensions. For a finite black hole surface gravity, the observer may choose higher frequency mode to keep high level entanglement. The fidelity of quantum teleporation is also reduced because of the Hawking-Unruh effect. We discuss the fidelity as a function of extra dimensions, mode frequency, black hole mass and black hole angular momentum parameter for both bosonic and fermionic resources.Comment: 15 pages, 10 figures,contents expande

Attitudes of students from south-east and east Asian countries to slaughter and transport of livestock

Attitudes to animals have been extensively studied for people in developed countries, but not for those in developing countries. The attitudes of prospective stakeholders in the livestock sectors in south-east and east Asia toward transport and slaughter were examined by surveying university students studying veterinary medicine and animal science in Malaysia, Thailand, China and Vietnam, with a total of 739 students taking part. Students had greater acceptability of transport than slaughter issues for livestock, and female students found most transport and slaughter issues of greater concern than male students. Veterinary students were more accepting of several issues than animal science students, in particular killing animals that were injured or ill. Religion had a major effect on attitudes. Muslim students found using animals that died naturally for products least acceptable. Compared to them, Hindu students were less accepting of killing injured or ill animals and Buddhist students less accepting of euthanasing healthy pets. Students with more experience of pets were less accepting of both transport and slaughter issues. It is concluded that concern was exhibited by future stakeholders in the SE and E Asian livestock industries for slaughter and, to a lesser extent, transport issues, although attitudes were influenced by their religion, gender and experience of pet-keeping

Edge and Bulk Transport in the Mixed State of a Type-II Superconductor

By comparing the voltage-current (V-I) curves obtained before and after cutting a sample of 2H-NbSe2, we separate the bulk and edge contributions to the transport current at various dissipation levels and derive their respective V- I curves and critical currents. We find that the edge contribution is thermally activated across a current dependent surface barrier. By contrast the bulk V-I curves are linear, as expected from the free flux flow model. The relative importance of bulk and edge contributions is found to depend on dissipation level and sample dimensions. We further show that the peak effect is a sharp bulk phenomenon and that it is broadened by the edge contribution