Magnetic anisotropy in dysprosium single crystals

Two single crystals were grown by using the strain-anneal technique. Three rectangular parallelepiped samples were cut from these crystals with the long dimension directed along one of the hexagonal axes. These are designated as the \u3c1120\u3e a-axis, the \u3c1oTo\u3e b-axis, and the \u3c0001 \u3e c-axis

Thermal expansion of rare earth metals

A high temperature dilatometric investigation of the rare earth metals was undertaken as part of a broad program of study of these elements, the ultimate goal being better understanding of metals in general. The more immediate goal, in addition to determining the coefficients of expansion quantitatively, was to detect evidence of any crystalline transformations which may occur and particularly to cast some light on certain high temperature transitions already discovered in several of these metals. The rare earth metals included in this investigation were lanthanum, cerium, praseodymium, neodymium, gadolinium, terbium, dysprosium, erbium, and ytterbium

Magnetic Order Beyond RKKY in the Classical Kondo Lattice

We study the Kondo lattice model of band electrons coupled to classical spins, in three dimensions, using a combination of variational calculation and Monte Carlo. We use the weak coupling `RKKY' window and the strong coupling regime as benchmarks, but focus on the physically relevant intermediate coupling regime. Even for modest electron-spin coupling the phase boundaries move away from the RKKY results, the non interacting Fermi surface no longer dictates magnetic order, and weak coupling `spiral' phases give way to collinear order. We use these results to revisit the classic problem of 4f magnetism and demonstrate how both electronic structure and coupling effects beyond RKKY control the magnetism in these materials.Comment: 6 pages, 4 figs. Improved figures, expanded captions. To appear in Europhys. Let

Intermediate Valence Model for the Colossal Magnetoresistance in Tl_{2}Mn_{2}O_{7}

The colossal magnetoresistance exhibited by Tl_{2}Mn_{2}O_{7} is an interesting phenomenon, as it is very similar to that found in perovskite manganese oxides although the compound differs both in its crystalline structure and electronic properties from the manganites. At the same time, other pyrochlore compounds, though sharing the same structure with Tl_{2}Mn_{2}O_{7}, do not exhibit the strong coupling between magnetism and transport properties found in this material. Mostly due to the absence of evidence for significant doping into the Mn-O sublattice, and the tendency of Tl to form conduction bands, the traditional double exchange mechanism mentioned in connection with manganites does not seem suitable to explain the experimental results in this case. We propose a model for Tl_{2}Mn_{2}O_{7} consisting of a lattice of intermediate valence ions fluctuating between two magnetic configurations, representing Mn-3d orbitals, hybridized with a conduction band, which we associate with Tl. This model had been proposed originally for the analysis of intermediate valence Tm compounds. With a simplified treatment of the model we obtain the electronic structure and transport properties of Tl_{2}Mn_{2}O_{7}, with good qualitative agreement to experiments. The presence of a hybridization gap in the density of states seems important to understand the reported Hall data.Comment: 8 pages + 5 postscript fig

At the intersection of globalization and "civilizational originality' : cultural production in Putin's Russia

This special issue originates from a transnational collaboration of scholars in philology, comparative literature, social theory, sociology, anthropology, ethnography, and media studies. The collection strives to advance a research agenda built on the nexus of three intellectual and academic domains: post-Soviet Russian cultural studies', the research paradigm put forward by Cultural Studies, as well as empirical methods developed in sociology. The collection illustrates the importance of expanding the experience of Cultural Studies beyond its established spheres of national investigation, while it also speaks to the necessity to re-evaluate the hegemony of the English-language academic and cultural production on the global scale. The collection offers insights into the gamut of cultural practices and institutional environments in which Russian cultural production happens today. It shows how cultural industries and institutions in Russia are integrated into the global marketplace and transnational communities, while they also draw on and contribute to local lives and experiences by trying to create an autonomous space for symbolic production at personal and collective levels. Through diverse topics, the issue sheds light on the agency, i.e. practitioners and participants, creators and consumers, of Russian cultural production and the neoliberal practices implemented on creative work and cultural administration in Russia today. The Introduction outlines the development of academic studies on Russian cultural practices since 1991; describes main political developments shaping the cultural field in Putin's Russia; and, finally, identifies the Cultural Studies debates the editors of the collection find most productive for investigations of Russia, i.e. the instrumentalization of culture and culture as resource. Relocated in an analysis of a post-socialist society, these conceptualisations seem increasingly problematic in a situation where local and federal policies governing cultural and creative work focus simultaneously on marketization and on nationalism as the main tools of legitimizing the federal government.Peer reviewe

Electrical Resistivity of Lanthanum, Praseodymium, Neodymium, and Samarium

The electrical resistivities of polycrystalline samples of La, Pr, Nd, and Sm are reported in the temperature range 1.3 to 300 deg K. La exhibits a superconducting transition at 5.8 deg K. The curve for Pr has slope changes at 61 and 95 deg K. The Nd curve shows small jumps at 5 and 20 deg K. Sm shows slope changes at 14 and 106 deg K. (auth

One Europe or None? Monism, Involution and Relations with Russia

The crisis in relations between Russia and the European Union (EU) is part of the broader breakdown of the post-Cold War security order. This commentary focuses on structural interpretation and identifies four interlinked processes shaping the crisis: tension between the logic of the enlargement and transformation; a dynamic of involution and resistance; the problem of monism, whereby the expanding self is unable adequately to engage with the un-integrated other; and the recent emergence of ‘other Europes’ that may potentially overcome involution. The erosion of the Atlantic system provides an opportunity for delayed institutional and ideational innovation

Europe and the political: from axiological monism to pluralistic dialogism

“The political” represents a moment in which actors recognise autonomy and equality as constitutive values in the agonistic search for appropriate open-ended political outcomes. The tutelary, pedagogical and disciplinary practices of the depoliticised European Union (EU) undermine the foundations of equality in diplomatic and political engagement between continental actors. The relationship becomes axiological, where issues are deemed to have been resolved through some sort of anterior pre-political arrangement. This is a type of ahistorical political monism that ultimately claims to speak for all of Europe. The return of “the political” allows a more generous and pluralistic politics to emerge based on genuine dialogical foundations in which self and other engage as equals and are mutually transformed by that engagement