664 research outputs found
Divergence of the dielectric constant in ultrathin granular metal films near the percolation threshold
We report on the electronic and optical properties of ultrathin granular films. We demonstrate that the static dielectric constant increases with thickness in the dielectric regime and diverges at the critical thickness, as predicted by classical percolation theory. However, for thicker samples, the dc conductivity does not obey scaling laws due to the presence of tunneling conduction. In this region the dielectric constant is positive, and the electronic transport is not metallic but can be described by Jonscher's universal power law, even though there is a Drude-like response indicating the presence of free charge carriers. Only for thicker films when the dielectric constant becomes negative is there metallic conduction
Multimode Quantitative Scanning Microwave Microscopy of In Situ Grown Epitaxial Ba\u3csub\u3e1-x\u3c/sub\u3eSr\u3csub\u3ex\u3c/sub\u3eTiO\u3csub\u3e3\u3c/sub\u3e Composition Spreads
We have performed variable-temperature multimode quantitative microwavemicroscopy of in situepitaxial Ba1âxSrxTiO3 thin-film composition spreads fabricated on (100) LaA1O3 substrates. Dielectric properties were mapped as a function of continuously varying composition from BaTiO3 to SrTiO3. We have demonstrated nondestructive temperature-dependent dielectric characterization of local thin-film regions. Measurements are simultaneously taken at multiple resonant frequencies of the microscope cavity. The multimode measurements allow frequency dispersion studies. We observe strong composition-dependent dielectric relaxation in Ba1âxSrxTiO3 at microwave frequencies
Pregnancy and childbirth in English prisons : institutional ignominy and the pains of imprisonment
© 2020 The Authors. Sociology of Health & Illness published by John Wiley & Sons Ltd on behalf of Foundation for SHIL.With a prison population of approximately 9000 women in England, it is estimated that approximately 600 pregnancies and 100 births occur annually. Despite an extensive literature on the sociology of reproduction, pregnancy and childbirth among women prisoners is underâresearched. This article reports an ethnographic study in three English prisons undertaken in 2015â2016, including interviews with 22 prisoners, six women released from prison and 10 staff members. Pregnant prisoners experience numerous additional difficulties in prison including the ambiguous status of a pregnant prisoner, physical aspects of pregnancy and the degradation of the handcuffed or chained prisoner during visits to the more public setting of hospital. This article draws on Erving Goffman's concepts of closed institutions, dramaturgy and mortification of self, Crewe et al.'s work on the gendered pains of imprisonment and Crawley's notion of âinstitutional thoughtlessnessâ, and proposes a new concept of institutional ignominy to understand the embodied situation of the pregnant prisoner.Peer reviewe
The interview as narrative ethnography : seeking and shaping connections in qualitative research.
Acts of counter-subjectification in qualitative research are always present but are often submerged in accounts that seek to locate the power of subjectification entirely with the researcher. This is particularly so when talking to people about sensitive issues. Based on an interview-based study of infertility and reproductive disruption among British Pakistanis in Northeast England, we explore how we, as researchers, sought and were drawn into various kinds of connections with the study participants; connections that were actively and performatively constructed through time. The three of us that conducted interviews are all female academics with Ph.Ds in anthropology, but thereafter our backgrounds, life stories and experiences diverge in ways that intersected with those of our informants in complex and shifting ways. We describe how these processes shaped the production of narrative accounts and consider some of the associated analytical and ethical implications
Giant positive magnetoresistance in metallic VOx thin films
We report on giant positive magnetoresistance effect observed in VOx thin
films, epitaxially grown on SrTiO3 substrate. The MR effect depends strongly on
temperature and oxygen content and is anisotropic. At low temperatures its
magnitude reaches 70% in a magnetic field of 5 T. Strong electron-electron
interactions in the presence of strong disorder may qualitatively explain the
results. An alternative explanation, related to a possible magnetic
instability, is also discussed.Comment: 4 pages, 5 figures included in the text, references update
Translanguaging and translation: the construction of social difference across city spaces
This paper considers the construction of social difference in the interactions of a couple as they communicate at home and work, with one another, their colleagues, and strangers in a superdiverse English city. In our linguistic ethnographic approach we observed, wrote field notes, audio-recorded key participants, took photographs, made video-recordings, and conducted interviews. We documented the role translanguaging and translation played and showed how these social practices varied across the cityâs spatial realms as different kinds of relationships are brought into play. While the interactions can be thematically characterized as broadly about money, business, and commerce, they can also be said to draw on widely circulating discourses about social and linguistic difference. We found that the construction of difference varied qualitatively by the distance and intimacy of the relationships in play. We also found that a translanguaging repertoire was particularly evident in navigating sensitive cultural activities, attitudes and beliefs. This points to the usefulness of translanguaging to signpost an openness to, and interest in, social and linguistic diversity in the market place, where buying and selling are the order of the day
Ferromagnetism in laser deposited anatase TiCoO_{2-\delta} films
Pulsed laser deposited films of Co doped anatase TiO2 are examined for Co
substitutionality, ferromagnetism, transport, magnetotransport and optical
properties. Our results show limited solubility (up to ~ 2 %) of Co in the
as-grown films and formation of Co clusters thereafter. For Ti0.93Co0.07O2-d
sample, which exhibits a Curie temperature (Tc) over 1180 K, we find the
presence of 20-50 nm Co clusters as well as a small concentration of Co
incorporated into the remaining matrix. After being subjected to the high
temperature anneal during the first magnetization measurement, the very same
sample shows a Tc ~ 650 K and almost full matrix incorporation of Co. This Tc
is close to that of as-grown Ti0.99Co0.01O2-d sample (~ 700 K). The transport,
magnetotransport and optical studies also reveal interesting effects of the
matrix incorporation of Co. These results are indicative of an intrinsic
Ti1-xCoxO2-d diluted magnetic semiconductor with Tc of about 650-700 K.Comment: 14 pages + 9 figure
'Working outâ identity: distance runners and the management of disrupted identity
This article contributes fresh perspectives to the empirical literature on the sociology of the body, and of leisure and identity, by analysing the impact of long-term injury on the identities of two amateur but serious middle/long-distance runners. Employing a symbolic interactionist framework,and utilising data derived from a collaborative autoethnographic project, it explores the role
of âidentity workâ in providing continuity of identity during the liminality of long-term injury and
rehabilitation, which poses a fundamental challenge to athletic identity. Specifically, the analysis
applies Snow and Andersonâs (1995) and Perinbanayagamâs (2000) theoretical conceptualisations
in order to examine the various forms of identity work undertaken by the injured participants, along
the dimensions of materialistic, associative and vocabularic identifications. Such identity work was
found to be crucial in sustaining a credible sporting identity in the face of disruption to the running
self, and in generating momentum towards the goal of restitution to full running fitness and reengagement
with a cherished form of leisure.
KEYWORDS: identity work, symbolic interactionism, distance running, disrupted identit
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