Noncollinear magnetic phases and edge states in graphene quantum Hall bars

Application of a perpendicular magnetic field to charge neutral graphene is expected to result in a variety of broken symmetry phases, including antiferromagnetic, canted, and ferromagnetic. All these phases open a gap in bulk but have very different edge states and noncollinear spin order, recently confirmed experimentally. Here we provide an integrated description of both edge and bulk for the various magnetic phases of graphene Hall bars making use of a noncollinear mean field Hubbard model. Our calculations show that, at the edges, the three types of magnetic order are either enhanced (zigzag) or suppressed (armchair). Interestingly, we find that preformed local moments in zigzag edges interact with the quantum spin Hall like edge states of the ferromagnetic phase and can induce backscattering.

Edge states in graphene-like systems

The edges of graphene and graphene like systems can host localized states with evanescent wave function with properties radically different from those of the Dirac electrons in bulk. This happens in a variety of situations, that are reviewed here. First, zigzag edges host a set of localized non-dispersive state at the Dirac energy. At half filling, it is expected that these states are prone to ferromagnetic instability, causing a very interesting type of edge ferromagnetism. Second, graphene under the influence of external perturbations can host a variety of topological insulating phases, including the conventional quantum Hall effect, the quantum anomalous Hall (QAH) and the quantum spin Hall phase, in all of which phases conduction can only take place through topologically protected edge states. Here we provide an unified vision of the properties of all these edge states, examined under the light of the same one orbital tight-binding model. We consider the combined action of interactions, spin–orbit coupling and magnetic field, which produces a wealth of different physical phenomena. We briefly address what has been actually observed experimentally.

Catalogue of type specimens of trilobites in Field Museum of Natural History / [by] Matthew H. Nitecki -- and Julia Golden --.

v.22(1970)

Ordovician vertebrates from Western United States / Robert H. Denison --

v.16:no.6(1967)

With or without you...judging politically in the field of Area of Freedom, Security and Justice? Research Papers in Law, 3/2007

From the Introduction. The study of the European Court of Justice’s (ECJ) case law of the regarding the Area of Freedom Security and Justice (AFSJ) is fascinating in many ways.1 First, almost the totality of the relevant case law is extremely recent, thereby marking the first ‘foundational’ steps in this field of law. This is the result of the fact that the AFSJ was set up by the Treaty of Amsterdam in 1997 and only entered into force in May 1999.2 Second, as the AFSJ is a new field of EU competence, it sets afresh all the fundamental questions – both political and legal – triggered by European integration, namely in terms of: a) distribution of powers between the Union and its member states, b) attribution of competences between the various EU Institutions, c) direct effect and supremacy of EU rules, d) scope of competence of the ECJ, and e) measure of the protection given to fundamental rights. The above questions beg for answers which should take into account both the extremely sensible fields of law upon which the AFSJ is anchored, and the EU’s highly inconvenient three-pillar institutional framework.3 Third, and as a consequence of the above, the vast majority of the ECJ’s judgments relating to the AFSJ are a) delivered by the Full Court or, at least, the Grand Chamber, b) with the intervention of great many member states and c) often obscure in content. This is due to the fact that the Court is called upon to set the foundational rules in a new field of EU law, often trying to accommodate divergent considerations, not all of which are strictly legal.4 Fourth, the case law of the Court relating to the AFSJ, touches upon a vast variety of topics which are not necessarily related to one another. This is why it is essential to limit the scope of this study. The content of, and steering for, the AFSJ were given by the Tampere European Council, in October 1999. According to the Tampere Conclusions, the AFSJ should consist of four key elements: a) a common immigration and asylum policy, b) judicial cooperation in both civil and penal matters, c) action against criminality and d) external action of the EU in all the above fields. Moreover, the AFSJ is to a large extent based on the Schengen acquis. The latter has been ‘communautarised’5 by the Treaty of Amsterdam and further ‘ventilated’ between the first and third pillars by decisions 1999/435 and 1999/436.6 Judicial cooperation in civil matters, mainly by means of international conventions (such as the Rome Convention of 1981 on the law applicable to contractual obligations) and regulations (such as (EC) 44/20017 and (EC) 1348/20008) also form part of the AFSJ. However, the relevant case law of the ECJ will not be examined in the present contribution.9 Similarly, the judgments of the Court delivered in the course of Article 226 EC proceedings against member states, will be omitted.10 Even after setting aside the above case law and notwithstanding the fact that the AFSJ only dates as far back as May 1999, the judgments of the ECJ are numerous. A simple (if not simplistic) categorisation may be between, on the one hand, judgments which concern the institutional setting of the AFSJ (para. 2) and, on the other, judgments which are related to some substantive AFSJ policy (para. 3).

National Minorities, Nationalizing States, and External National Homelands in the New Europe. Notes toward a Relational Analysis. Institute of Advanced Studies Political Science Series, 11 December 1993

Nationalism remains central to politics in and among the new nation-states. Far from »solving« the region's national question, the most recent reconfiguration of political space – the replacement of the Soviet Union, Yugoslavia, and Czechoslovakia by some twenty would-be nation-states – only recast it in a new form. It is this new phase and form of the national question that I explore in this paper. I begin by outlining a particular relational configuration – the triadic relational nexus between national minorities, nationalizing states, and external national homelands – that is central to the national question in post-Soviet Eurasia. In the second, and most substantial, section of the paper, I argue that each of the »elements« in this relational nexus – minority, nationalizing state, and homeland – should itself be understood in dynamic and relational terms, not as a fixed, given, or analytically irreducible entity but as a field of differentiated positions and an arena of struggles among competing »stances.« In a brief concluding section, I return to the relational nexus as a whole, underscoring the dynamically interactive quality of the triadic interplay.

Drivers of agricultural capital productivity in selected EU member states. Factor Markets Working Paper No. 30, September 2012

The aim of this Working Paper is to provide an empirical analysis of the marginal return on working capital and fixed capital in agriculture, based on data gathered by the Farm Accountancy Data Network from seven EU member states. Particular emphasis is placed on the detection of credit market imperfections. The key idea is to provide farm group-specific estimates of the shadow price of capital, and to use these to analyse the drivers of on-farm capital use in European agriculture. Based on Cobb Douglas estimates of farm-type specific production functions, we find that working capital is typically used in more than economically optimal quantities and often displays negative marginal returns across countries and farm types. This is less often the case with regard to fixed capital, but it is only in a small set of sectors where access to fixed capital appears severely constrained. These sectors include field crop and mixed farms in Denmark, dairy farms in East Germany, as well as mixed farms in Italy and the UK. The relationship between farm financial indicators and the estimated shadow prices of capital varies considerably across countries and sectors. Among the farms with a high shadow price for fixed capital in Denmark, high debt levels and little owned land tended to induce more intensive capital use, which may reflect the liberal Danish banking system. In East Germany, Italy and the UK, high debt levels made farmers more tightly capital constrained. Hence, in the latter group of countries, more traditional mechanisms of capital allocation based on debt capacity seemed to be at work. As a general conclusion, EU agriculture appears to be characterised by overcapitalisation rather than by credit constraints.

From Lampedusa to the Post-Stockholm Programme: Difficult European solidarity in the field of migration. European Policy Brief No. 24, March 2014

Solidarity is a founding principle of the European migration policy. To hold true, Member States must be faithful to their common commitment to European migration rules and implement fair burden sharing of the costs attached to border controls. However, solidarity among Member States appears altogether fragile and under threat, a situation that could jeopardise the founding principle of the free movement of persons in the European Union’s space. The recent solidarity crisis among Member States was solved by an increased externalisation of the European migration policy. Consequently, for the EU to live up to its values, it will have to prove itself generous towards third countries.

Basic Statistics of the Community. Comparison with some European countries, the United States of America and with the Union of Socialist Soviet Republics. Fourth Edition. November 1963

Population; national product; agriculture; energy; industry; transport; external trade; standard of living; trends of major economic indicators in the six; supplementary statistics on iron and steel-trends from 1952-62; supplementary statistics in an social field-employment, earnings, expenditure, social security

Russell Field runway improvements, Rome : environmental impact statement.

F only available in microfiche.

Areawide environmental assessment on the development of a NEPA compliance strategy for new source coal mining activity in the western Kentucky coal field /

Mode of access: Internet.

Field testing, application of combustion modifications to control pollutant emissions from industrial boilers : phase II /

Mode of access: Internet.

Bioremediation in the Field Search System (BFSS) : user documentation.

"August 1994."

Bioremediation in the Field Search System (BFSS) : user documentation.

"August 1995."

The Fabrication of polyethylene FML field seams /

"September 1989."