3,718 research outputs found
Intrinsic paramagnetic Meissner effect due to s-wave odd-frequency superconductivity
No full textIn 1933, Meissner and Ochsenfeld reported the expulsion of magnetic flux-the diamagnetic Meissner effect-from the interior of superconducting lead. This discovery was crucial in formulating the Bardeen-Cooper-Schrieffer (BCS) theory of superconductivity. In exotic superconducting systems BCS theory does not strictly apply. A classical example is a superconductor-magnet hybrid system where magnetic ordering breaks time-reversal symmetry of the superconducting condensate and results in the stabilization of an odd-frequency superconducting state. It has been predicted that under appropriate conditions, odd-frequency superconductivity should manifest in the Meissner state as fluctuations in the sign of the magnetic susceptibility, meaning that the superconductivity can either repel (diamagnetic) or attract (paramagnetic) external magnetic flux. Here, we report local probe measurements of faint magnetic fields in a Au=Ho=Nb trilayer system using low-energy muons, where antiferromagnetic Ho (4.5 nm) breaks time-reversal symmetry of the proximity-induced pair correlations in Au. From depth-resolved measurements below the superconducting transition of Nb, we observe a local enhancement of the magnetic field in Au that exceeds the externally applied field, thus proving the existence of an intrinsic paramagnetic Meissner effect arising from an odd-frequency superconducting state.Peer reviewe
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Origin and regenerative potential of vertebrate mechanoreceptor-associated stem cells
No full textWidera D, Hauser S, Kaltschmidt C, Kaltschmidt B. Origin and regenerative potential of vertebrate mechanoreceptor-associated stem cells. Anatomy Research International. 2012;2012:1-9.Meissner corpuscles and Merkel cell neurite complexes are highly specialized mechanoreceptors present in the hairy and glabrous skin, as well as in different types of mucosa. Several reports suggest that after injury, such as after nerve crush, freeze injury, or dissection of the nerve, they are able to regenerate, particularly including reinnervation and repopulation of the mechanoreceptors by Schwann cells. However, little is known about mammalian cells responsible for these regenerative processes. Here we review cellular origin of this plasticity in the light of newly described adult neural crest-derived stem cell populations. We also discuss further potential multipotent stem cell populations with the ability to regenerate disrupted innervation and to functionally recover the mechanoreceptors. These capabilities are discussed as in context to cellularly reprogrammed Schwann cells and tissue resident adult mesenchymal stem cells
Hjalmar Meissner (1885-1940)
No full textCarl Hjalmar Meissner was born 1 March 1865 in Helsinki, Finland and died 28 May 1940 in Stockholm. He was a Finnish-Swedish pianist, conductor, arranger, composer and author. As a conductor, he worked mainly as a bandleader for military music and theatre ensembles, but also as an opera and symphony orchestra conductor. His profession as a composer arose mostly from his work as pianist and conductor. He was married to operetta singer Emma Meissner in 1899.</p
Meissner-Ochsenfeld superconducting anomalies in the Be-Ag-F system
No full textWe report here observations of sudden drops in the magnetic susceptibility of a large number of samples in the Be-Ag-F system, over the temperatures ranging from 8.5 to 64 K. These magnetic anomalies, strongly reminiscent of the Meissner-Ochsenfeld effect, suggest the presence of superconductivity in a small sample fraction of this fluoroargentate system, a cousin of the oxocuprate High-TC materials. © 2003 Elsevier Ltd. All rights reserved
Mettlerkamp, der Führer einer am deutschen Freiheitskriege theilnehmenden Bürgerwehr : mit Benutzung des handschriftlichen Nachlasses Mettlerkamps
No full textvon Fr. WilleMit Exlibris von Conrad Ferdinand Meyer Exemplar der Zentralbibliothek Zürich, C.F.-Meyer-BibliothekAus dem Vorbesitz von Conrad Ferdinand Meyer Exemplar der Zentralbibliothek Zürich, C.F.-Meyer-Bibliothek"Herrn K F. Meyer / in freundschaftlicher Hochachtung u Sympath / der Verfasser" Exemplar der Zentralbibliothek Zürich, C.F.-Meyer-Bibliothe
Observation and control of hybrid spin-wave-Meissner-current transport modes
No full textSuperconductors are materials with zero electrical resistivity and the ability to expel magnetic fields, which is known as the Meissner effect. Their dissipationless diamagnetic response is central to magnetic levitation and circuits such as quantum interference devices. In this work, we used superconducting diamagnetism to shape the magnetic environment governing the transport of spin waves-collective spin excitations in magnets that are promising on-chip signal carriers-in a thin-film magnet. Using diamond-based magnetic imaging, we observed hybridized spin-wave-Meissner-current transport modes with strongly altered, temperature-tunable wavelengths and then demonstrated local control of spin-wave refraction using a focused laser. Our results demonstrate the versatility of superconductor-manipulated spin-wave transport and have potential applications in spin-wave gratings, filters, crystals, and cavities.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.QN/vanderSarlabQN/Kavli Nanolab DelftQN/Blanter Grou
Development of a magnetic susceptibility measurement system for detecting the Meissner effect
No full textapplication/pdfTo identify the superconducting phase transition at low temperatures, we construct a measurement system for detecting the Meissner effect. The well-known method of the measurement system is the Hartshorn-type bridge, but we try to construct the simplified measurement system, where the cylinder of the primary coil and that of secondary ones are settle in a fixed geometrical arrangement without the Hartshorn-type bridge. In our study, we use an alternative magnetic field of HAC = H0sin(2πft) with H0 ~ 1.6 Oe and 12 < f < 4000 Hz. To test our measurement system, we measured the magnetic susceptibility of niobium and obtained very sharp and clear Meissner signal at around 8.2 K.departmental bulletin pape
The Role of Foreign Currency Debt in Financial Crises: 1880-1913 vs. 1972-1997
No full textWhat is the role of foreign currency debt in precipitating financial crises? In this paper we compare the 1880 to 1913 period to recent experience. We examine debt crises, currency crises, banking crises and the interrelation between these varieties of crises. We pay special attention to the role of hard currency debt, currency mismatches and debt intolerance. We find fairly robust evidence that high exposure to foreign currency debt does not necessarily lead to a high chance of having a debt crisis, currency crisis, or a banking crisis. A key finding is some countries do not suffer from great financial fragility despite high exposure to original sin. In the nineteenth century, the British offshoots and Scandinavia generally avoided severe financial meltdowns while today many advanced countries have high original sin but have had few financial crises. The common denominator in both periods is that currency mismatches matter. A strong reserve position or high exports relative to hard currency liabilities helps decrease the likelihood of a debt crisis, currency crisis or a banking crisis. This strengthens the evidence for the hypothesis that foreign currency debt is dangerous when mis-managed. We discuss the robustness of these results and make some general comparisons based on this evidence from over 60 years of intense international capital market integration.
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