Microwave properties of HTS (high temperature superconductor) films

Conference · Mon Jan 01 00:00:00 EST 1990

OSTI ID:6825881

Cooke, D W; Arendt, P N; Gray, E R; Muenchausen, R E; Bennett, B L; Foltyn, S R; Estler, R C; Wu, X D; Reeves, G A; Elliott, N E; Brown, D R ^[1]; Portis, A M ^[2]; Taber, R C ^[3]; Mogro-Campero, A ^[4]

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1. Los Alamos National Lab., NM (USA)
2. California Univ., Berkeley, CA (USA)
3. Hewlett-Packard Corp., Palo Alto, CA (USA). Labs.
4. General Electric Co., Schenectady, NY (USA). Corporate Research and Development Ce

High-frequency applications of high-temperature superconductors generally fall into two categories: devices that require low values of surface resistance R{sub s} in ambient surface magnetic fields H{sub rf}, and devices that require low R{sub s} in modest fields. Moreover, many applications can be realized with small-surface-area films whereas others require larger areas-radiofrequency (rf) cavities, for example. Regardless of the application, the potential of HTS films is predicated on satisfying one or both of the above-stated requirements. We have measured the surface resistance of small-area (1 cm{sup 2}) and large-area (6.5 cm{sup 2}) YBa{sub 2}Cu{sub 3}O{sub 7} (YBCO) films that have been laser ablated onto LaA{ell}O{sub 3} substrates, large-area (5.1 cm{sup 2}) YBCO films that have been e-beam deposited onto LaA{ell}O{sub 3}, and large-area (11.4 cm{sup 2}) T{ell}-based films that have been magnetron sputtered onto metallic substrates. The best R{sub s} values are obtained from the 1-cm{sup 2} laser-ablated films; they are 40 {mu}{Omega} and 340 {mu}{Omega} at 4 K and 77 K, respectively ({omega}/2{pi} = 10 GHz). Comparable values for Cu are 6 and 13 m{Omega}, respectively. Large-area T{ell}-based films yield typical R{sub s} values of 4 m{Omega} and 14 m{Omega} at 4 K and 77 K, respectively ({omega}/2{pi} = 18 GHz). The dependence of R{sub s} on H{sub rf} for these films indicates that surface fields as large as 55 Oe can be achieved with R{sub s} increasing only by a factor of 10. This field dependence is associated with c-axis texturing.

• Research Organization: Los Alamos National Lab., NM (USA)
• Sponsoring Organization: DOE/ER
• DOE Contract Number: W-7405-ENG-36; AC03-76SF00098
• OSTI ID: 6825881
• Report Number(s): LA-UR-90-3268; CONF-901105-12; ON: DE91000211
• Resource Relation: Conference: Fall meeting of the Materials Research Society, Boston, MA (USA), 24 Nov - 1 Dec 1990
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
HIGH-TC SUPERCONDUCTORS
PHYSICAL PROPERTIES
BARIUM COMPOUNDS
COPPER OXIDES
ELECTRIC CONDUCTIVITY
FREQUENCY DEPENDENCE
LASER RADIATION
MAGNETIC FIELDS
MICROWAVE RADIATION
SPUTTERING
SUBSTRATES
SURFACE PROPERTIES
TEMPERATURE DEPENDENCE
YTTRIUM COMPOUNDS
ALKALINE EARTH METAL COMPOUNDS
CHALCOGENIDES
COPPER COMPOUNDS
ELECTRICAL PROPERTIES
ELECTROMAGNETIC RADIATION
OXIDES
OXYGEN COMPOUNDS
RADIATIONS
SUPERCONDUCTORS
TRANSITION ELEMENT COMPOUNDS
360204* - Ceramics
Cermets
& Refractories- Physical Properties
656100 - Condensed Matter Physics- Superconductivity