Magnus Force in High Temperature Superconductivity and Berry Phase

In the topological framework of high temperature superconductivity we have discussed the Magnus force acting on its vortices

Keypad mobile phones are associated with a significant increased risk of microbial contamination compared to touch screen phones

The use of mobile phones in the clinical environment by healthcare workers has become widespread. Despite evidence that these devices can harbour pathogenic micro-organisms there is little guidance on how to reduce contamination. Recently touchscreen phones with a single flat surface have been introduced. We hypothesise that bacterial contamination of phones used in hospitals will be lower on touchscreen devices compared to keypad devices. Sixty seven mobile phones belonging to health care workers were sampled. The median colony count for touchscreen phones and keypad devices was 0·09 colony forming units (cfu)/cm2 (interquartile range (IQR) 0.05–0·14) and 0·77 cfu/cm2 (IQR range 0·45–3.52) respectively. Colony counts were significantly higher on the keypad phones (Fisher’s exact test p<0.001). Multivariate analysis showed the type of phone (keypad vs. touch screen) was associated with increased colony counts (F-statistic 14.13: p<0.001). Overall, nine (13%) phones grew either meticillin resistant Staphylococcus aureus or vancomycin resistant enterococci. Eight (24%) keypad phones were contaminated with these organisms compared with one touch screen phone (3%). Our data indicate that touchscreen mobile phones are less contaminated than their keypad counterparts, and they are less likely to harbour pathogenic bacteria in the clinical setting

FACt: FORTRAN toolbox for calculating fluctuations in atomic condensates

We develop a FORTRAN code to compute fluctuations in atomic condensates (FACt) by solving the Bogoliubov-de Gennes (BdG) equations for two component Bose-Einstein condensate (TBEC) in quasi two dimensions. The BdG equations are recast as matrix equations and solved self consistently. The code is suitable for handling quantum fluctuations as well as thermal fluctuations at temperatures below the critical point of Bose-Einstein condensation. The code is versatile, and the ground state density profile and low energy excitation modes obtained from the code can be easily adapted to compute different properties of TBECs -- ground state energy, overlap integral, quasi particle amplitudes of BdG spectrum, dispersion relation and structure factor and other related experimental observables.Comment: The manuscript contains 28 pages and 6 figures. The code including sample input file and README file can be found in a tar file 'hfb2d2s.tar' by clicking on the "other formats" in the paper download pag

High TcT_c Superconductivity, Skyrmions and the Berry Phase

It is here pointed out that the antiferromagnetic spin fluctuation may be associated with a gauge field which gives rise to the antiferromagnetic ground state chirality. This is associated with the chiral anomaly and Berry phase when we consider the two dimensional spin system on the surface of a 3D sphere with a monopole at the centre. This realizes the RVB state where spinons and holons can be understood as chargeless spins and spinless holes attached with magnetic flux. The attachment of the magnetic flux of the charge carrier suggest, that this may be viewed as a skyrmion. The interaction of a massless fermion representing a neutral spin with a gauge field along with the interaction of a spinless hole with the gauge field enhances the antiferromagnetic correlation along with the pseudogap at the underdoped region. As the doping increases the antiferromagnetic long range order disappears for the critical doping parameter $\delta_{sc}$. In this framework, the superconducting pairing may be viewed as caused by skyrmion-skyrmion bound states.Comment: 10 pages, accepted in Phys. Rev.

Experimental Evaluation of Indoor Localization Methods for Industrial IoT Environment

294-307With the evolution of new technology, GPS brings a lot of revolution in the Localization system but it is not an effective solution in Indoor Environment. This is because of the fact that the signals coming from the satellite are attenuated, absorbed, scattered by the walls, roofs, and other objects. Due to this, lots of errors may arise in the system. To overcome this problem sensor node based localization system is used for mobile IoT domain. Recently, in IoT based system, various sensor nodes have been used in different kinds of localization based applications such as Location-Based Services (LBS) and Proximity-Based Services (PBS). However, such sensor nodes may not be stable in every environment to provide an accurate positioning. Although there are different localization techniques are available to find out the location of any object, but there is a common challenge of finding best localization technique suitable for most of the environment. This work investigates different existing indoor localization methods for its practical suitability in Lab and actual Industrial environment for deployment on IoT nodes. A mobile application has also been developed to implement four state-of-the-art localization techniques for getting the position and calculating its accuracy in different environments. During the experiment, BLE Beacons are used as sensor nodes due to their ease of deployment, lower complexity, lower cost, and higher power consumption. The error in the accuracy of estimated position got calculated in terms of Average Error. According to the experimental result in real environments it has been revealed that the Weighted Centroid Localization technique provides better accuracy in industrial as well as laboratory environment

Soft Electromagnetic Radiations from Relativistic Heavy Ion Collisions

The production of low mass dileptons and soft photons from thermalized Quark Gluon Plasma (QGP) and hadronic matter in relativistic heavy ion collisions is evaluated. A boost invariant longitudinal and cylindrically symmetric transverse expansion of the systems created in central collision of lead nuclei at CERN SPS, BNL RHIC, and CERN LHC, and undergoing a first order phase transition to hadronic matter is considered. A large production of low mass (M< 0.3 GeV) dileptons, and soft photons (p_T< 0.4 GeV) is seen to emanate from the bremsstrahlung of quarks and pions. We find an increase by a factor of 2--4 in the low mass dilepton and soft photon yield as we move from SPS to RHIC energies, and an increase by an order of magnitude as we move from SPS to LHC energies. Most of the soft radiations are found to originate from pion driven processes at SPS and RHIC energies, while at the LHC energies the quark and the pion driven processes contribute by a similar amount. The study of the transverse mass distribution is seen to provide interesting details of the evolution. We also find a unique universal behaviour for the ratio of M^2 weighted transverse mass distribution for M= 0.1 GeV to that for M= 0.2 and 0.3 GeV, as a function of M_T, for SPS, RHIC, and LHC energies, in the absence of transverse expansion of the system. A deviation from this universal behaviour is seen as a clear indication of the flow.Comment: Revtex fil