DocumentCode :
87393
Title :
Microwave Response of Coaxial Cavities Made of Bulk Magnesium Diboride
Author :
Gallitto, Aurelio Agliolo ; Camarda, P. ; Li Vigni, Maria ; Albisetti, Alessandro Figini ; Saglietti, Luca ; Giunchi, Giovanni
Author_Institution :
Dipt. di Fis. e Chim., Univ. di Palermo, Palermo, Italy
Volume :
24
Issue :
1
fYear :
2014
fDate :
Feb. 2014
Firstpage :
13
Lastpage :
21
Abstract :
We report on the microwave properties of coaxial cavities built by using bulk MgB2 superconductor prepared by reactive liquid Mg infiltration technology. We have assembled a homogeneous cavity by using an outer MgB2 cylinder and an inner MgB2 rod and a hybrid cavity by using an outer copper cylinder and the same MgB2 rod as inner conductor. By the analysis of the resonance curves, in the different resonant modes, we have determined the microwave surface resistance Rs of the MgB2 materials as a function of the temperature and the frequency, in the absence of dc magnetic fields. At T=4.2 K and f ≈ 2.5 GHz, by an mw pulsed technique, we have determined the quality factor of the homogeneous cavity as a function of the input power up to a maximum level of about 40 dBm (corresponding to a maximum peak magnetic field of about 100 Oe). Contrary to what occurs in many films, Rs of the MgB2 material used does not exhibit visible variations up to an input power level of about 10 dBm and varies less than a factor of 2 on further increasing the input power of 30 dB.
Keywords :
Q-factor; magnesium compounds; superconducting cavity resonators; superconducting materials; surface resistance; MgB2; bulk magnesium diboride; coaxial cavities; hybrid cavity; microwave response; microwave surface resistance; quality factor; reactive liquid infiltration technology; resonance curves; temperature 4.2 K; Cavity resonators; Conductors; Materials; Powders; Q-factor; Superconducting microwave devices; Temperature measurement; Cavity resonators; superconducting microwave (mw) devices; surface impedance;
fLanguage :
English
Journal_Title :
Applied Superconductivity, IEEE Transactions on
Publisher :
ieee
ISSN :
1051-8223
Type :
jour
DOI :
10.1109/TASC.2013.2289928
Filename :
6658838
Link To Document :
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