80 research outputs found
Type-I superconductivity in ScGa3 and LuGa3 single crystals
We present evidence of type-I superconductivity in single crystals of ScGa3
and LuGa3, from magnetization, specific heat, and resistivity measurements: low
critical temperatures Tc = 2.1-2.2 K; field-induced secondto first-order phase
transition in the specific heat, critical fields less than 240 Oe; and low
Ginzburg-Landau coefficients {\kappa} approx 0.23 and 0.30 for ScGa3 and LuGa3,
respectively, are all traits of a type-I superconducting ground state. These
observations render ScGa3 and LuGa3 two of only several type-I superconducting
compounds, with most other superconductors being type II (compounds and alloys)
or type I (elemental metals and metaloids).Comment: 5 pages, 6 figure
Resonant torsion magnetometry in anisotropic quantum materials
Unusual behavior of quantum materials commonly arises from their effective
low-dimensional physics, which reflects the underlying anisotropy in the spin
and charge degrees of freedom. Torque magnetometry is a highly sensitive
technique to directly quantify the anisotropy in quantum materials, such as the
layered high-T superconductors, anisotropic quantum spin-liquids, and the
surface states of topological insulators. Here we introduce the magnetotropic
coefficient , the second derivative of the
free energy F with respect to the angle between the sample and the
applied magnetic field, and report a simple and effective method to
experimentally detect it. A sub-g crystallite is placed at the tip of a
commercially available atomic force microscopy cantilever, and we show that
can be quantitatively inferred from a shift in the resonant frequency under
magnetic field. While related to the magnetic torque , takes the role of torque susceptibility, and thus provides
distinct insights into anisotropic materials akin to the difference between
magnetization and magnetic susceptibility. The thermodynamic coefficient is
discontinuous at second-order phase transitions and subject to Ehrenfest
relations with the specific heat and magnetic susceptibility. We apply this
simple yet quantitative method on the exemplary cases of the Weyl-semimetal NbP
and the spin-liquid candidate RuCl, yet it is broadly applicable in quantum
materials research.Comment: 7 pages including 6 figures and methods sectio
Public political narratives: developing a neglected source through the exploratory case of Russia in the Putin-Medvedev era
The place of narrative in political science is an issue that resurfaces with regularity, usually focusing on the questions of generalisability, evidence and causality which lie at the heart of the discipline. Most such debate concerns the use of narrative by political scientists. Far less attention has been devoted to the use of narrative by political actors, despite its relative ubiquity. Even where such attention has been given, it concentrates less on the narrative per se, and more on its performance and impact. However, the nature of public political narratives means that analysis of them facilitates a holistic understanding of their narrators' politics. A public political narrative consists of a sequential account given by political actors connecting selected, specific developments so as to impose a desired order on them. Taking contemporary Russia as an exploratory case, narrative analysis draws out the motivations, world view and inconsistencies within the Putin-Medvedev regime. Recurring motifs and symbols identify the regime's political priorities, explaining policy choices and revealing future concerns. Narrative has a predictive aspect, identifying likely policy responses to unexpected events. Narratives capture time, and shifts in their temporalities indicate changes in self-conceptualisation and political priorities. Temporal appropriations include or exclude particular agential and causal explanations. The relationship between their plots and subplots represents a political signalling process. Public political narratives provide temporally and spatially specific exceptionalist accounts, but their combinatory quality also facilitates comparative analysis. The approach essayed here provides methodological generalisability, arguing that the neglect of public political narratives merits correcting
Scenario analysis report with policy recommendations: An assessment of sustainability, resilience, efficiency and fairness and effective chain relationships in VALUMICS case studies : Deliverable 8.4
This is an open access article distributed under the Creative Commons Attribution License, to view a copy of the license, see: https://creativecommons.org/licenses/by/4.0/. The final version of this report is available at https://doi.org/10.5281/zenodo.6534011The functioning of food value chains entails a complex organisation from farm to fork which is characterised by various governance forms and externalities which have shaped the overall food system. VALUMICS food value chain case studies: wheat to bread, dairy cows to milk, beef cattle to steak, farmed salmon to fillets and tomato to processed tomato were selected to enable explorative and empirical analysis to better understand the functioning of the food system and, to identify the main challenges that need to be addressed to improve sustainability, integrity, resilience, and fairness of European food chains. The VALUMICS system analysis was executed through four operational phases starting with Groundwork & analysis including mapping specific attributes and impacts of food value chains and their externalities. This was followed by Case study baseline analysis, which provided input to the third phase on Modelling and exploration of future scenarios and finally Policy and synthesis of the overall work. This report is an overall synthesis of the VALUMICS results as follows: • Key findings from the VALUMICS project on the functioning of European food value chains and their impacts on more sustainable, resilient, fairer, and transparent food system are summarised through a compilation of 25 Research Findings and Policy Briefs. • By highlighting the major contributions from the research activities throughout the four phases of the VALUMICS project, this report delivers an assessment of various factors influencing sustainability, resilience, efficiency and fairness and effective chain relationships of different food value chains, and their determinants. • The synthesis of the outcome allows the identification of opportunities and challenges characterising the functioning of food supply chains, and thus, the prospects and potentials for strengthening the EU food sector
- …