Magnetic field induced rotation of the d-vector in Sr_2RuO_4

The superconductor Sr_2RuO_4 is widely believed to be a spin triplet system with a chiral order parameter analogous to the A phase of superfluid helium-3. The best evidence for this pairing state is that the Knight shift or spin susceptibility measured in neutron scattering is constant below T_c, unlike in a spin-singlet superconductor. The original Knight shift and neutron scattering measurements were performed for magnetic fields aligned in the ruthenate a-b plane. These would be consistent with a triplet d-vector d{k} aligned along the c-axis. However recently the Knight shift for fields along c was also found to be constant below T_c, which is not expected for this symmetry state. In this paper we show that while spin-orbit interaction stabilises the c-axis oriented d-vector, it is possible that only a very small external B field may be sufficient to rotate the d-vector into the a-b plane. In this case the triplet pairing model remains valid. We discuss characteristics of the transition and the prospects to detect it in thermodynamic quantities.Comment: 2 pages, 1 figure, Proceedings of the M2S-HTSC conference in Dresden. Requires elsart.sty (included

Family, obligations, and migration

The aim of this paper is to investigate the influence of family and kin networks on the individual decision to migrate. The study is based on qualitative ethnographic data which was collected during a field research in Cameroon in spring 2005, showing the considerable impact of the extended family on the migrant’s choice to leave Cameroon for Germany. Migrants do not solely move for their own achievements and purposes, but rather as significant members of their entire immediate family. The individual is part of an informal reciprocal system of exchange which is based on trust and has social consequences, and includes duties and responsibilities for both sides.anthropology, Cameroon, family networks, migration

Marriage over space and time among male migrants from Cameroon to Germany

Restrictive immigration and integration policies in Germany increasingly force African migrants to develop strategies and practices to acquire legal residence and obtain an essential work permit. Our account of Cameroonian men in Germany contributes to the discussion about the role of the nation state in transnational migration processes. Since national policies in the receiving country determine the right to settle and the risk of expulsion, the German nation state plays a decisive role for African migrants. The present paper emphasises the impact of national migration policies on Cameroonian men’s marriage strategies. Diminishing options for legalising their status in Germany by other means make Cameroonians increasingly dependent on sustaining a three-year marriage to a German wife. Mainly based on extensive ethnographic fieldwork in Cameroon and Germany, the present article explores the distribution of marriage over space and time as a means of securing the right to work and stay in Germany.Cameroon, Germany, international migration, marriage

Team work: A problem for Ergonomics?

This Article does not have an abstrac

Family, obligations, and migration: the role of kinship in Cameroon

The aim of this paper is to investigate the influence of family and kin networks on the individual decision to migrate. The study is based on qualitative ethnographic data collected during field research in Cameroon and shows the considerable impact of the extended family on the migrant’s decision to leave Cameroon for Germany. Migrants do not necessarily set out to pursue individual goals. They are often delegated to leave by authority figures in their extended family. The individual is part of an informal reciprocal system of exchange, which is based on trust, has social consequences, and includes duties and responsibilities for both sides.Cameroon, Germany, decision making, kinship, migration, race relations, remittances