Title :
Microwave surface resistance of YBa2Cu3O7-δ
Author :
Kobayashi, Mineo ; Okabe, Katsuya ; Tanuma, Seiichi ; Sankawa, Izumi ; Sato, Makoto ; Konaka, Tsuneo ; Ishihara, Koshi
Author_Institution :
Nat. Lab. for High Energy Phys., Ibaraki, Japan
fDate :
3/1/1989 12:00:00 AM
Abstract :
The magnetic-field dependence of the microwave surface resistance of both single crystals and sintered crystals of YBa2Cu3 O7-δ (YBCO) has been measured at 24 GHz. The resistance decreases below the superconducting transition temperature and reaches a constant residual resistance. The value is much lower for single crystals than for polycrystals. Furthermore, polycrystals showed magnetoresistance at low field and magnetoresistance with hysteresis at high field, which resembles the magnetization behavior of typical type-II superconductors. The observed magnetoresistance is shown to be inherent to a sintered polycrystal which is composed of grains and contains many voids. The single crystal showed lower magnetoresistance
Keywords :
barium compounds; electric resistance measurement; high-temperature superconductors; magnetoresistance; microwave measurement; yttrium compounds; 24 GHz; YBa2Cu3O7-δ; constant residual resistance; grains; high temperature superconductor; magnetic-field dependence; magnetization behavior; magnetoresistance; microwave surface resistance; sintered crystals; superconducting transition temperature; type-II superconductors; voids; Crystals; Electrical resistance measurement; Magnetic field measurement; Magnetic hysteresis; Magnetoresistance; Microwave measurements; Superconducting magnets; Superconducting transition temperature; Surface resistance; Yttrium barium copper oxide;
Journal_Title :
Magnetics, IEEE Transactions on
