Depairing Current at High Magnetic Fields in Vortex-Free High-Temperature Superconducting Nanowires

Autor: Teresa Puig, Anna Palau, Gian Paolo Papari, Alvaro Sanchez, V. Rouco, Carles Navau, Nuria Del-Valle, Xavier Obradors, Francesco Tafuri, Davide Massarotti, Daniela Stornaiuolo
Přispěvatelé: Ministerio de Economía y Competitividad (España), European Commission, Generalitat de Catalunya, Rouco, V., Navau, C., Del-Valle, N., Massarotti, D., Papari, G. P., Stornaiuolo, D., Obradors, X., Puig, T., Tafuri, F., Sanchez, A., Palau, A.
Rok vydání: 2019
Předmět:
Zdroj: Digital.CSIC. Repositorio Institucional del CSIC
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ISSN: 1530-6992
Popis: Superconductors are essential in many present and future technologies, from large-scale devices for medical imaging, accelerators, or fusion experiments to ultra-low-power superconducting electronics. However, their potential applicability, and particularly that of high-temperature superconductors (HTS), is severely affected by limited performances at large magnetic fields and high temperatures, where their use is most needed. One of the main reasons for these limitations is the presence of quantized vortices, whose movements result in losses, internal noise, and reduced performances. The conventional strategy to overcome the flow of vortices is to pin them along artificial defects. Here, we theoretically and experimentally demonstrate that critical-current density in high-temperature superconductors can reach unprecedented high values at high fields and temperatures by preventing vortex entry. By tailoring the geometry, that is, reducing the width, W, of nanowire-patterned HTS films, the range of the Meissner state, for which no vortices are present, is extended up to very large applied field values, on the order of ∼1 T. Current densities on the order of the depairing current can be sustained under high fields for a wide range of temperatures. Results may be relevant both for devising new conductors carrying depairing-current values at high temperatures and large magnetic fields and for reducing flux noise in sensors and quantum systems.
We acknowledge financial support from Spanish Ministry of Economy and Competitiveness through the “Severo Ochoa” Programme for Centres of Excellence (SEV-2015-0496), COACHSUPENERGY project (MAT2014-51778-C2-1-R), and SuMaTe (RTI2018-095853-B-C21) cofinanced by the European Regional Development Fund, and project MAT2016-79426-P (Agencia Estatal de Investigacion/Fondo ́ Europeo de Desarrollo Regional). We also thank support from the European Union for NANOCOHYBRI project (Cost Action CA 16218) and from the Catalan Government projects SGR-2017-1519 and 2017-SGR-105. A.S. acknowledges a grant from ICREA Academia, funded by the Generalitat de Catalunya. V.R. Acknowledges EU H2020 research and innovation programme (Marie Sklodowska-Curie IF grant agreement OXWALD 838693). We acknowledge the use of ICTS-CNM facilities and ICMAB scientific and technical services. We thank Alexey V. Pan for fruitful discussions.
Databáze: OpenAIRE