Residual losses in epitaxial thin films of YBa2Cu3O7 from microwave to submillimeter wave frequencies
- 28 October 1991
- journal article
- research article
- Published by AIP Publishing in Applied Physics Letters
- Vol. 59 (18) , 2326-2328
- https://doi.org/10.1063/1.106058
Abstract
We have measured the residual loss in five epitaxial a‐b plane films of the high‐Tc superconductor YBa2Cu3O7. Microwave measurements near 10 GHz were made by resonance techniques at 4 K. Submillimeter measurements from ∼1.5 to 21 THz were made at 2 K by a direct absorption technique. We use a model of weakly coupled superconducting grains and a homogeneous two‐fluid model to fit the data for each film below the well‐known absorption edge at 13.5 THz. When the penetration depth determined from muon spin rotation measurements is used to constrain each model, the weakly coupled grain model is able to fit the measured absorptivities for all films, but the two‐fluid model is less successful.Keywords
This publication has 16 references indexed in Scilit:
- Far-Infrared and Microwave Intragap Absorption in a YBa 2 Cu 3 O 7-δ Thin Film at Low TemperatureEurophysics Letters, 1991
- The microwave surface impedance of high-T/sub c/ superconductorsIEEE Transactions on Magnetics, 1991
- Frequency- and temperature-dependent conductivity in crystalsPhysical Review B, 1990
- Far-infrared reflectivity and absorptivity of YBa2Cu3O7-δ thin filmsPhysica B: Condensed Matter, 1990
- YBa2Cu3O7−δ superconducting films with low microwave surface resistance over large areasApplied Physics Letters, 1990
- I n s i t u grown YBa2Cu3O7−d thin films from single-target magnetron sputteringApplied Physics Letters, 1989
- Microstructure of i n s i t u epitaxially grown superconducting Y-Ba-Cu-O thin filmsApplied Physics Letters, 1989
- Far-Infrared Reflectivity and Dynamical Conductivity of an Epitaxial YBa 2 Cu 3 O 7-δ Thin FilmEurophysics Letters, 1989
- Weakly coupled grain model of high-frequency losses in high T c superconducting thin filmsApplied Physics Letters, 1988
- As-deposited high T c and J c superconducting thin films made at low temperaturesApplied Physics Letters, 1988