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Title: Fabrication and radio frequency test of large-area MgB 2 films on niobium substrates

Abstract

Magnesium diboride (MgB 2) is a promising candidate material for superconducting radio frequency (RF) cavities because of its higher transition temperature and critical field compared with niobium. To meet the demand of RF test devices, the fabrication of large-area MgB 2 films on metal substrates is needed. Here, in this work, high quality MgB 2 films with 50 mm diameter were fabricated on niobium by using an improved HPCVD system at Peking University, and RF tests were carried out at SLAC National Accelerator Laboratory. The transition temperature is approximately 39.6 K and the RF surface resistance is about 120 μΩ at 4 K and 11.4 GHz. Finally, the fabrication processes, surface morphology, DC superconducting properties and RF tests of these large-area MgB 2 films are presented.

Authors:
 [1];  [1];  [2];  [3];  [2];  [2];  [3];  [1]
  1. Peking Univ., Beijing (China). School of Physics, State Key Lab. of Nuclear Physics and Technology
  2. SLAC National Accelerator Lab., Menlo Park, CA (United States)
  3. Peking Univ., Beijing (China). School of Physics and State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, Applied Superconductivity Research Center
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE; National Science Foundation (NSF)
OSTI Identifier:
1379941
Grant/Contract Number:
AC02-76SF00515; 11575012; 51177160; 2011CB808303; 2011CBA00104; LQ13E070002
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Superconductor Science and Technology
Additional Journal Information:
Journal Volume: 30; Journal Issue: 4; Journal ID: ISSN 0953-2048
Publisher:
IOP Publishing
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; large-area MgB2 flim; Nb substrate; HPCVD; cryogenic RF test; surface resistance

Citation Formats

Ni, Zhimao, Guo, Xin, Welander, Paul B., Yang, Can, Franzi, Matthew, Tantawi, Sami, Feng, Qingrong, and Liu, Kexin. Fabrication and radio frequency test of large-area MgB2 films on niobium substrates. United States: N. p., 2017. Web. doi:10.1088/1361-6668/aa5aa0.
Ni, Zhimao, Guo, Xin, Welander, Paul B., Yang, Can, Franzi, Matthew, Tantawi, Sami, Feng, Qingrong, & Liu, Kexin. Fabrication and radio frequency test of large-area MgB2 films on niobium substrates. United States. doi:10.1088/1361-6668/aa5aa0.
Ni, Zhimao, Guo, Xin, Welander, Paul B., Yang, Can, Franzi, Matthew, Tantawi, Sami, Feng, Qingrong, and Liu, Kexin. Thu . "Fabrication and radio frequency test of large-area MgB2 films on niobium substrates". United States. doi:10.1088/1361-6668/aa5aa0. https://www.osti.gov/servlets/purl/1379941.
@article{osti_1379941,
title = {Fabrication and radio frequency test of large-area MgB2 films on niobium substrates},
author = {Ni, Zhimao and Guo, Xin and Welander, Paul B. and Yang, Can and Franzi, Matthew and Tantawi, Sami and Feng, Qingrong and Liu, Kexin},
abstractNote = {Magnesium diboride (MgB2) is a promising candidate material for superconducting radio frequency (RF) cavities because of its higher transition temperature and critical field compared with niobium. To meet the demand of RF test devices, the fabrication of large-area MgB2 films on metal substrates is needed. Here, in this work, high quality MgB2 films with 50 mm diameter were fabricated on niobium by using an improved HPCVD system at Peking University, and RF tests were carried out at SLAC National Accelerator Laboratory. The transition temperature is approximately 39.6 K and the RF surface resistance is about 120 μΩ at 4 K and 11.4 GHz. Finally, the fabrication processes, surface morphology, DC superconducting properties and RF tests of these large-area MgB2 films are presented.},
doi = {10.1088/1361-6668/aa5aa0},
journal = {Superconductor Science and Technology},
number = 4,
volume = 30,
place = {United States},
year = {Thu Jan 19 00:00:00 EST 2017},
month = {Thu Jan 19 00:00:00 EST 2017}
}

Journal Article:
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