39 research outputs found
ESR study of the spin ladder with uniform Dzyaloshinskii-Moria interaction
Evolution of the ESR absorption in a strong-leg spin ladder magnet
(CHN)CuBr (abbreviated as DIMPY) is studied from 300K to
400mK. Temperature dependence of the ESR relaxation follows a staircase of
crossovers between different relaxation regimes. We ague that the main
mechanism of ESR line broadening in DIMPY is uniform Dzyaloshinskii-Moria
interaction (K) with an effective longitudinal component along
an exchange bond of Cu ions within the legs resulting from the low crystal
symmetry of DIMPY and nontrivial orbital ordering. The same
Dzyaloshinskii-Moriya interaction results in the lifting of the triplet
excitation degeneracy, revealed through the weak splitting of the ESR
absorption at low temperatures.Comment: 13 pages, submitted to PRB, Fig.3 update
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