Title :
Thin-film HTS probe coils for magnetic-resonance imaging
Author :
Withers, R.S. ; Liang, G.-C. ; Cole, B.F. ; Johansson, M.
Author_Institution :
Conductus Inc., Sunnyvale, CA, USA
fDate :
3/1/1993 12:00:00 AM
Abstract :
Several planar coil designs, with integral resonating capacitors, are reported using large-area sputtered YBCO films. One design utilizes a distributed interdigital capacitor, while a second exploits capacitive coupling of two films on opposite sides of a dielectric. Devices of the first design made on LaAlO/sub 3/ have achieved Q>10/sup 4/ at 18.5 MHz, possibly limited by the loss tangent of this substrate. Identical coils made with silver films have Q=10. With the second design, Q>10/sup 4/ was achieved at the even lower frequency of 5.7 MHz.<>
Keywords :
Q-factor; barium compounds; biomedical NMR; biomedical electronics; biomedical equipment; coils; high-temperature superconductors; probes; superconducting magnets; superconducting thin films; thin film devices; yttrium compounds; 18.5 MHz; 5.7 MHz; LaAlO/sub 3/; MRI; YBa/sub 2/Cu/sub 3/O/sub 7/-LaAlO/sub 3/; capacitive coupling; distributed interdigital capacitor; integral resonating capacitors; large area sputtered films; loss tangent; magnetic-resonance imaging; planar coil designs; probe coils; Capacitors; Coils; Dielectric substrates; Dielectric thin films; High temperature superconductors; Magnetic films; Probes; Silver; Sputtering; Yttrium barium copper oxide;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
