Coexistence of Antiferromagnetism and Superconductivity in Electron-doped High-Tc Superconductors

We present magnetotransport evidence for antiferromagnetism in films of the electron-doped cuprates Pr$_{2-x}$Ce$_x$CuO$_4$. Our results show clear signature of static antiferromagnetism up to optimal doping x=0.15, with a quantum phase transition close to x=0.16, and a coexistence of static antiferromagnetism and superconductivity for 0.12$\le$x$\le$0.15

Gapped tunneling spectra in the normal state of Pr2−x_{2-x}Cex_xCuO4_4

We present tunneling data in the normal state of the electron doped cuprate superconductor Pr$_{2-x}$Ce$_x$CuO$_4$ for three different values of the doping $x$. The normal state is obtained by applying a magnetic field greater than the upper critical field, $H_{c2}$ for $T < T_c$. We observe an anomalous normal state gap near the Fermi level. From our analysis of the tunneling data we conclude that this is a feature of the normal state density of states. We discuss possible reasons for the formation of this gap and its implications for the nature of the charge carriers in the normal and the superconducting states of cuprate superconductors.Comment: 7 pages ReVTeX, 11 figures files included, submitted to PR

An examination of the effects of self-regulatory focus on the perception of the media richness: the case of email

Communication is a key element in organizations’ business success. The media richness theory and the channel expansion theory are two of the most influential theories regarding the selection and use of communication media in organizations; however, literature has focused little on the effects of self-regulation by managers and employees in these theories. To analyze these topics, this study develops an empirical investigation by gathering data from 600 managers and employees using a questionnaire. The results suggest that the perception of media richness is positively affected when the individual shows a promotion focus or strategy.Peer ReviewedPostprint (author’s final draft

Ultrafast dynamics in the presence of antiferromagnetic correlations in electron-doped cuprate La2−x_{2-x}Cex_xCuO4±δ_{4\pm\delta}

We used femtosecond optical pump-probe spectroscopy to study the photoinduced change in reflectivity of thin films of the electron-doped cuprate La$_{2-x}$Ce$_x$CuO$_4$ (LCCO) with dopings of x$=$0.08 (underdoped) and x$=$0.11 (optimally doped). Above T$_c$, we observe fluence-dependent relaxation rates which onset at a similar temperature that transport measurements first see signatures of antiferromagnetic correlations. Upon suppressing superconductivity with a magnetic field, it is found that the fluence and temperature dependence of relaxation rates is consistent with bimolecular recombination of electrons and holes across a gap (2$\Delta_{AF}$) originating from antiferromagnetic correlations which comprise the pseudogap in electron-doped cuprates. This can be used to learn about coupling between electrons and high-energy ($\omega>2\Delta_{AF}$) excitations in these compounds and set limits on the timescales on which antiferromagnetic correlations are static

Role of oxygen in the electron-doped superconducting cuprates

We report on resistivity and Hall measurements in thin films of the electron-doped superconducting cuprate Pr$_{2-x}$Ce$_{x}$CuO$_{4\pm\delta}$. Comparisons between x = 0.17 samples subjected to either ion-irradiation or oxygenation demonstrate that changing the oxygen content has two separable effects: 1) a doping effect similar to that of cerium, and 2) a disorder effect. These results are consistent with prior speculations that apical oxygen removal is necessary to achieve superconductivity in this compound.Comment: 5 pages, 5 figure

The investigation of vertebral injury sustained during aircrew ejection. Phase 2a - Basic science experimental design and investigation of dynamic characteristics of vertebral columns considered as an engineering structure Annual report, 1 Nov. 1966 - 31 Oct. 1967

Dynamic strength studies on human vertebrae for correlation with data on effects of forcible ejection from disabled aircraf

Alterity & sensitivity in inter-organizational relations: contours of the tutor in marketing ethics education.

Purpose & literature addressed: This paper scrutinises the way in which ethics is taught in the modern business/industrial marketing syllabus. We argue for a reappraisal of the tutor-student relationship such that we may facilitate a greater understanding of how marketing students can make sense of themselves and of ‘the other’ within industrial networks. Research method: This paper is conceptual in its approach. Drawing on literature from the history of marketing thought, educational philosophy and the work of Emmanuel Levinas, we suggest that the conceptualisation of ethics in marketing cannot be divorced from the question of pedagogy and the responsibilities of the tutor. Research findings: We suggest that the ideas of alterity and proximity offers space for a discussion of justice within the global supply chain, providing entry into the marketing discourse for those members of the industrial network not normally encountered by students in the course of teaching. Main contribution: Importantly for teachers of inter-organizational relationships, Levinas offers an opportunity to simultaneously re-imagine the relationship between the student and the tutor. In the process we are forced to confront and acknowledge the responsibility that the role of a moral mediator entails

Alterity and sensitivity: contours of the tutor in marketing ethics education.

This paper attempts to (re)plot the contours of the Tutor by scrutinising the way in which ethics is taught in the modern marketing syllabus. We open up a debate on how the Tutor role as a conduit of apparent ethical knowledge to students has somehow failed to map with sufficient sensitivity the terrain of the moral impulse in business practice. In particular, we argue for a reappraisal of the Tutor/student relationship such that we may facilitate a greater understanding of how marketing students can make sense of themselves and of ‗the other‘. Drawing on literature from educational philosophy and the work of Emmanuel Levinas, we suggest that the conceptualisation of ethics in marketing cannot be divorced from the question of pedagogy and the responsibilities of the tutor. Whilst the largely conventional model adopted for the teaching of marketing may provide students with a prescribed set of knowledge and skills, it may by the same token refuse us the moral education that seems to be necessary. The paper concludes that that recent economic problems offer an opportunity for a reappraisal of the teaching of marketing ethics. It is an opportunity to re-imagine the relationship between the student and the tutor