Submillimeter and microwave residual losses in epitaxial films of Y-Ba-Cu-O and Tl-Ca-Ba-Cu-O
- Lawrence Berkeley Lab., CA (United States)
- Conductus, Inc., Sunnyvale, CA (United States)
- Stanford Univ., CA (United States). Dept. of Applied Physics
- Bell Communications Research, Inc., Red Bank, NJ (United States)
- Sandia National Labs., Albuquerque, NM (Unite
We have used a novel bolometric technique and a resonant technique to obtain accurate submillimeter and microwave residual loss data for epitaxial thin films of YBa{sub 2}Cu{sub 3}O{sub 7}, Tl{sub 2}Ca{sub 2}Ba{sub 2}Cu{sub 3}O{sub 10} and Tl{sub 2}CaBa{sub 2}Cu{sub 2}O{sub 8}. For all films we obtain good agreement between the submillimeter and microwave data, with the residual losses in both the Y-Ba-Cu-O and Tl-Ca-Ba-Cu-O films scaling approximately as frequency squared below {approximately} 1 THz. We are able to fit the losses in the Y-Ba-Cu-O films to a weakly coupled grain model for the a-b plane conductivity, in good agreement with results from a Kramers-Kronig analysis of the loss data. We observe strong phonon structure in the Tl-Ca-Ba-Cu-O films for frequencies between 2 and 21 THz, and are unable to fit these losses to the simple weakly coupled grain model. This is in strong contrast to the case for other high {Tc} superconductors such as YBa{sub 2}Cu{sub 3}O{sub 7}, where phonon structure observed in ceramic samples is absent in epitaxial oriented films and crystals because of the electronic screening due to the high conductivity of the a-b planes.
- Research Organization:
- Lawrence Berkeley Lab., CA (United States)
- Sponsoring Organization:
- USDOE; USDOD; CRSSE; USDOE, Washington, DC (United States); Department of Defense, Washington, DC (United States); Center for Research in Superconductivity and Superconductivity Electronics (United States)
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 7282597
- Report Number(s):
- LBL-32148; CONF-9204169-1; ON: DE92017075
- Resource Relation:
- Conference: 2. symposium on high temperature superconductors in high frequency fields, Santa Fe, NM (United States), 1-3 Apr 1992
- Country of Publication:
- United States
- Language:
- English
Similar Records
Submillimeter and microwave residual losses in epitaxial films of Y-Ba-Cu-O and Tl-Ca-Ba-Cu-O
Submillimeter and microwave residual losses in epitaxial films of Y-Ba-Cu-O and Tl-Ca-Ba-Cu-O
Related Subjects
HIGH-TC SUPERCONDUCTORS
AC LOSSES
SUPERCONDUCTING FILMS
BARIUM OXIDES
CALCIUM OXIDES
COPPER OXIDES
ELECTRIC CONDUCTIVITY
MICROSTRUCTURE
THALLIUM OXIDES
YTTRIUM OXIDES
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
CALCIUM COMPOUNDS
CHALCOGENIDES
COPPER COMPOUNDS
CRYSTAL STRUCTURE
ELECTRICAL PROPERTIES
ENERGY LOSSES
FILMS
LOSSES
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
SUPERCONDUCTORS
THALLIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
360207* - Ceramics
Cermets
& Refractories- Superconducting Properties- (1992-)
360204 - Ceramics
Cermets
& Refractories- Physical Properties