Influence of the Dzyaloshinskii-Moriya exchange interaction on quantum phase interference of spins

Magnetization measurements of a Mn12mda wheel single-molecule magnet with a spin ground state of S = 7 show resonant tunneling and quantum phase interference, which are established by studying the tunnel rates as a function of a transverse field applied along the hard magnetization axis. Dzyaloshinskii-Moriya (DM) exchange interaction allows the tunneling between different spin multiplets. It is shown that the quantum phase interference of these transitions is strongly dependent on the direction of the DM vector.Comment: 5 pages, 5 figure

Feminisms, gender and social media: public and political performativities regarding sexual harassment in Cyprus

This article draws from research on feminism, politics, social media and everyday sexism in Cyprus to examine the power dynamics between discourses of misogyny and feminism as produced in the public sphere. It focuses on how Facebook was utilised as both a digital space for feminist resistance and misogyny in two case studies which involve one female and two male MPs. At the crossroads of emancipatory and hegemonic particularities, we discuss how feminisms and social media operate in the socio-temporal context of the public and political sphere of Cyprus

Fabrication of Nano-Gapped Single-Electron Transistors for Transport Studies of Individual Single-Molecule Magnets

Three terminal single-electron transistor devices utilizing Al/Al2O3 gate electrodes were developed for the study of electron transport through individual single-molecule magnets. The devices were patterned via multiple layers of optical and electron beam lithography. Electromigration induced breaking of the nanowires reliably produces 1-3 nm gaps between which the SMM can be situated. Conductance through a single Mn12(3-thiophenecarboxylate) displays the coulomb blockade effect with several excitations within +/- 40 meV.Comment: 10 pages, 5 figure

Three-Loop Results in QCD with Wilson Fermions

We calculate the third coefficient of the lattice beta function in QCD with Wilson fermions, extending the pure gauge results of Luescher and Weisz; we show how this coefficient modifies the scaling function on the lattice. We also calculate the three-loop average plaquette in the presence of Wilson fermions. This allows us to compute the lattice scaling function both in the standard and energy schemes.Comment: 3 pages, LaTeX (fleqn.sty, espcrc2.sty), contribution to Lattice'97. Table caption corrected. The longer write-ups are in hep-lat/9801007 (beta function) and hep-lat/9801003 (plaquette

Physical and dynamical characterisation of low Delta-V NEA (190491) 2000 FJ10

We investigated the physical properties and dynamical evolution of Near Earth Asteroid (NEA) (190491) 2000 FJ10 in order to assess the suitability of this accessible NEA as a space mission target. Photometry and colour determination were carried out with the 1.54 m Kuiper Telescope and the 10 m Southern African Large Telescope during the object's recent favourable apparition in 2011-12. During the earlier 2008 apparition, a spectrum of the object in the 6000-9000 Angstrom region was obtained with the 4.2 m William Herschel Telescope. Interpretation of the observational results was aided by numerical simulations of 1000 dynamical clones of 2000 FJ10 up to 10^6 yr in the past and in the future. The asteroid's spectrum and colours determined by our observations suggest a taxonomic classification within the S-complex although other classifications (V, D, E, M, P) cannot be ruled out. On this evidence, it is unlikely to be a primitive, relatively unaltered remnant from the early history of the solar system and thus a low priority target for robotic sample return. Our photometry placed a lower bound of 2 hrs to the asteroid's rotation period. Its absolute magnitude was estimated to be 21.54+-0.1 which, for a typical S-complex albedo, translates into a diameter of 130+-20 m. Our dynamical simulations show that it has likely been an Amor for the past 10^5 yr. Although currently not Earth-crossing, it will likely become so during the period 50 - 100 kyr in the future. It may have arrived from the inner or central Main Belt > 1 Myr ago as a former member of a low-inclination S-class asteroid family. Its relatively slow rotation and large size make it a suitable destination for a human mission. We show that ballistic Earth-190491-Earth transfer trajectories with Delta-V < 2 km s^-1 at the asteroid exist between 2052 and 2061.Comment: 2 Tables, 11 Figures, accepted for publication in Astronomy & Astrophysic

Tourists’ perceptions regarding the use of anthropomorphic robots in tourism and hospitality

Purpose Amidst the COVID-19 outbreak, service organizations rushed to deploy robots to serve people in quarantine, again igniting the ongoing dispute regarding robots in tourism. This study aims to investigate tourists’ perceptions regarding the use of robots and, more specifically, anthropomorphic robots in the tourism domain. Design/methodology/approach A qualitative inquiry was used to delve deep into the issue of tourists’ perceptions regarding the usage of anthropomorphic robots in tourism, with a total number of 78 interviews with tourists being retained in the study. Findings The findings reveal that tourists favor the use of anthropomorphic robots over any other type of robot. The use of anthropomorphic robots in tourism may result in an overall enhanced experiential value. Even so, informants also expressed frustration, sadness and disappointment vis-à-vis the use of robots in a human-driven industry. Research limitations/implications A conceptual continuum of tourists’ perceptions and concerns over the use of robots is presented that can guide future studies. Tourism stakeholders may look at the possibility of incorporating carefully designed anthropomorphic robots in key service positions, but should not give the impression that robots are replacing the human face of the organization. Practical implications Tourism stakeholders may look at the possibility of incorporating carefully designed anthropomorphic robots in key service positions, but should not give the impression that robots are replacing the human face of the organization. Originality/value Tourism organizations that make use of robots run the risk of being perceived as nonanthropocentric. This leads to the conclusion that anthropomorphism could be used but should not replace the sector’s anthropocentrism. The study conveys tourists’ concerns over technological (robot) determinism

Quantum tunneling in a three dimensional network of exchange coupled single-molecule magnets

A Mn4 single-molecule magnet (SMM) is used to show that quantum tunneling of magnetization (QTM) is not suppressed by moderate three dimensional exchange coupling between molecules. Instead, it leads to an exchange bias of the quantum resonances which allows precise measurements of the effective exchange coupling that is mainly due to weak intermolecular hydrogen bounds. The magnetization versus applied field was recorded on single crystals of [Mn4]2 using an array of micro-SQUIDs. The step fine structure was studied via minor hysteresis loops.Comment: 4 pages, 4 figure