Tunneling Anisotropic Magnetoresistance of Helimagnet Tunnel Junctions

We theoretically investigate the angular and spin dependent transport in normal-metal/helical-multiferroic/ferromagnetic heterojunctions. We find a tunneling anisotropic magnetoresistance (TAMR) effect due to the spiral magnetic order in the tunnel junction and to an effective spin-orbit coupling induced by the topology of the localized magnetic moments in the multiferroic spacer. The predicted TAMR effect is efficiently controllable by an external electric field due to the magnetoelectric coupling

Topological view on magnetic adatoms in graphene

We study theoretically the physical properties of a magnetic impurity in graphene. Within the Anderson model for a very strong Coulomb interaction on the impurity, we start from the Slave-Boson method and introduce a topological picture consisting of a degree of a map and a winding number (WN) to analyze the phase shift and the occupation on the impurity. The occupation is linked to WN. For a generic normal metal we find a fractional WN. In contrast, the winding is accelerated by the relativistic dispersion of graphene at half-filling leading to an integer occupation. We show that the renormalization parameter that shifts the impurity level is insufficient to invert the sign of the energy level. Consequently, the state at half-filling is stable unless a gate voltage is tuned such that the Fermi level touches the edge of the broadened impurity level. Only in this case the zero field susceptibility is finite and shows a pronounced peak structure with the gate voltage.Comment: 9pages. 4 figure

Casimir interactions of an object inside a spherical metal shell

We investigate the electromagnetic Casimir interactions of an object contained within an otherwise empty, perfectly conducting spherical shell. For a small object we present analytical calculations of the force, which is directed away from the center of the cavity, and the torque, which tends to align the object opposite to the preferred alignment outside the cavity. For a perfectly conducting sphere as the interior object, we compute the corrections to the proximity force approximation (PFA) numerically. In both cases the results for the interior configuration match smoothly onto those for the corresponding exterior configuration.Comment: 4 pages, 3 figure

Casimir potential of a compact object enclosed by a spherical cavity

We study the electromagnetic Casimir interaction of a compact object contained inside a closed cavity of another compact object. We express the interaction energy in terms of the objects' scattering matrices and translation matrices that relate the coordinate systems appropriate to each object. When the enclosing object is an otherwise empty metallic spherical shell, much larger than the internal object, and the two are sufficiently separated, the Casimir force can be expressed in terms of the static electric and magnetic multipole polarizabilities of the internal object, which is analogous to the Casimir-Polder result. Although it is not a simple power law, the dependence of the force on the separation of the object from the containing sphere is a universal function of its displacement from the center of the sphere, independent of other details of the object's electromagnetic response. Furthermore, we compute the exact Casimir force between two metallic spheres contained one inside the other at arbitrary separations. Finally, we combine our results with earlier work on the Casimir force between two spheres to obtain data on the leading order correction to the Proximity Force Approximation for two metallic spheres both outside and within one another.Comment: 12 pages, 6 figure

Constraints on stable equilibria with fluctuation-induced forces

We examine whether fluctuation-induced forces can lead to stable levitation. First, we analyze a collection of classical objects at finite temperature that contain fixed and mobile charges, and show that any arrangement in space is unstable to small perturbations in position. This extends Earnshaw's theorem for electrostatics by including thermal fluctuations of internal charges. Quantum fluctuations of the electromagnetic field are responsible for Casimir/van der Waals interactions. Neglecting permeabilities, we find that any equilibrium position of items subject to such forces is also unstable if the permittivities of all objects are higher or lower than that of the enveloping medium; the former being the generic case for ordinary materials in vacuum.Comment: 4 pages, 1 figur

Peranan Dewan Pengawas Syariah terhadap Praktik Kepatuhan Syariah dalam Perbankan Syariah di Indonesia

This research is to analyze the role of DPS (Dewan Pengawas Syariah or Sharia Supervisory Board) towards the practice of sharia obedience with the perspective of customer protection in sharia banking in Indonesia. This research adopted the analysis method based upon the doctrinal content by applying four types of legal approach including:Â (i) history; (ii) Fiqh/philosophy; (iii) comparison and (iv) analysis and critical. In addition, the approach alignment is also needed for the legislative alignment with Islamic philosophy and customer protection philosophy. The result of the research concluded that any violation in sharia obedience neglected by DPS will negatively impact the image and credibility of sharia banking to public; thus, it can bring an impact on the public trust. For this reason, the roles of DPS in sharia banking needs to be optimized, for instance related to the qualification of DPS appointment must be tighter and the support to its roles must be realized in sharia banking. DSN MUI as an institution issuing the fatwa (binding ruling) can make the coordination and equalize the perception with the DPS posted in sharia banks in Indonesia in supervising the operation of sharia bank to make it really playing a role and ready to run its task as the DPS

Guiding principles for good governance of the smart destination

Smart tourism development has received tremendous attention worldwide, but relevant literature remains largely focused on the technological aspects of achieving the greater economic growth and efficiency through innovation, mobility, inclusion and environmental sustainability the smart paradigm promises. While well-being and experience enhancement are considered at the individual level of tourists and (sometimes) residents, guiding principles for achieving responsible smart tourism at the destination level are lacking. Addressing these concerns, this paper begins to explore justice and ethics principles that offer the potential to help facilitate good governance of sustainable smart destinations. By merging smart tourism goals with justice and ethics considerations the paper presents preliminary guidelines for theory building, public policy and development practice in the context of smart destinations governance, and future research in this area. Keywords: smart tourism; sustainable development; governance, ethics, justice, responsible touris

Konstituen Kimia Minyak Atsiri Tiga Jenis Tumbuhan Famili Rutaceae [Chemical Constituents of Essential Oils From Three Species of Rutaceous Family Plant]

Hydrodistilation process of Feroniella lucida, Clausena harmandiana and Swinglea glutinosa leaves, 0.15%, 0.25 % and 0.20% essential oils were obtained respectively. The GC-MS analysis results shows the essential oil of Feroniella lucida contains w-desil ethanoate (38.23%), 1-decanol (11.01%), 1-decanol acetate (10.82%), and the essential oil of Clausena harmandiana contains a-pinene (12.23%) and copaene (12.40%).On the other hand, the essential oil of Swinglea glutinosa contains isocariophylene (10.09%), 3,3,7,7-tetramethyl-5-(2-methyl-l-prophenyl)-tricyclo 4.1.0.02.4 heptane (21.80%) and nerolidol type 2 (21.34%).