Correspondence between microwave and submillimeter absorptivity in epitaxial thin films of YBa[sub 2]Cu[sub 3]O[sub 7]

Journal Article · Wed Mar 31 23:00:00 EST 1993 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.47.8076· OSTI ID:6658017

Miller, D; Richards, P L ^[1]; Etemad, S; Inam, A; Venkatesan, T; Dutta, B; Wu, X D ^[2]; Eom, C B; Geballe, T H ^[3]; Newman, N; Cole, B F ^[4]

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1. Department of Physics, University of California, and Materials Sciences Division, Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States)
2. Bell Communications Research, Red Bank, New Jersey 07701 (United States)
3. Department of Applied Physics, Stanford University, Stanford California 94305 (United States)
4. Conductus, Inc., Sunnyvale, California 94086 (United States)

We have measured the low-temperature loss in six epitaxial [ital ab]-plane films of the high-[ital T][sub [ital c]] superconductor YBa[sub 2]Cu[sub 3]O[sub 7] over a factor of 2000 in frequency. Submillimeter measurements from 25 to 700 cm[sup [minus]1] were made at 2 K by a direct absorption technique in which the film acts as the absorbing element in a composite bolometric detector. Microwave measurements near 10 GHz (0.3 cm[sup [minus]1]) were made on five of the same films by resonance techniques at 4 K. The [similar to]0.4-[mu]m-thick films were grown epitaxially on SrTiO[sub 3], LaAlO[sub 3], and MgO by off-axis sputtering and laser deposition. The absorptivities measured for all films studied are qualitatively similar, increasing smoothly with frequency, with no gaplike features below the well-known absorption edge at 450 cm[sup [minus]1]. A successful three-parameter fit is obtained for all of our films. This fit can be interpreted either in terms of a weakly coupled grain model or a homogeneous two-fluid model with residual normal conductivity. The fitting parameters correspond to a grain-penetration depth [lambda][sub [ital g]] equal to the muon-spin-relaxation value of 140 nm, and to reasonable grain properties. They also give carrier densities in reasonable agreement with optically determined plasma frequencies and conductivities in agreement with a Kramers-Kronig analysis of the absorptivity data.

• DOE Contract Number: AC03-76SF00098
• OSTI ID: 6658017
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 47:13; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
ABSORPTIVITY
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
BARIUM OXIDES
CHALCOGENIDES
COPPER COMPOUNDS
COPPER OXIDES
CORRELATIONS
FILMS
FREQUENCY DEPENDENCE
HIGH-TC SUPERCONDUCTORS
KRAMERS-KRONIG CORRELATION
OPTICAL PROPERTIES
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
SUPERCONDUCTORS
THIN FILMS
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
YTTRIUM OXIDES