Claims
- 1. A multilayer structure comprising:
- at least one first epitaxial layer of a first copper-oxide perovskite material having a first non-distorted crystallographic lattice structural state with first unit cell dimensions when said first copper-oxide perovskite material is unstressed in bulk, said first copper-oxide perovskite material when unstressed in bulk exhibiting a first set of non-superconducting to superconducting electrical conduction parameters;
- at least one second epitaxial layer of a second copper-oxide perovskite material, said second epitaxial copper-oxide perovskite material being different in composition than said first copper-oxide perovskite material and having a second non-distorted crystallographic lattice structural state with second unit cell dimensions which differ from said first unit cell dimensions when said second copper-oxide perovskite material is unstressed in bulk, said second copper-oxide perovskite material when unstressed in bulk exhibiting a second set of non-superconducting to superconducting electrical conduction parameters,
- said first and second epitaxial layers being deposited one on the other so that crystallographic structures of said first and second copper-oxide perovskite materials in said layers are distorted relative to said first and second non-distorted crystallographic lattice structural states respectfully with at least one of said non-superconducting to superconducting electrical conduction parameters of said multilayer structure differing from a corresponding electrical conduction parameter of said first and second sets of normal to superconducting electrical conduction parameters as a result of the distortion relative to said first and second non-distorted crystallographic lattice structural states in which
- said first copper-oxide perovskite material is YBa.sub.2 CU.sub.3 O.sub.7-.delta. ;
- said first undistorted crystallographic lattice structural state is an orthorhombic crystal structure with "a" and "b" unit cell dimensions of approximately 3.83 .ANG. and 3.88 .ANG. respectively for .delta. close to zero;
- said second copper-oxide perovskite material is Nd.sub.1.83 Ce.sub.0.17 CUO.sub.4.+-.Y ; and
- said second undistorted crystallographic structural state is an tetragonal crystal structure with "a" and "b" unit cell dimensions approximately equal to 3.95 .ANG..
- 2. The multilayer structure of claim 1 wherein:
- the distorted crystallographic structures of said first and second copper-oxide perovskite material layers both have "a" and "b" unit cell dimensions approximately equal to 3.88 .ANG..
CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation of application Ser. No. 07/892,599 filed on May 29, 1992, now abandoned, which is a continuation of application Ser. No. 07/420,842, filed 13 Oct. 1989, now abandoned.
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
5071828 |
Greuter et al. |
Oct 1991 |
|
5087604 |
Shiga et al. |
Feb 1992 |
|
5096882 |
Kato et al. |
Mar 1992 |
|
Foreign Referenced Citations (1)
Number |
Date |
Country |
0329507 |
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EPX |
Continuations (2)
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Number |
Date |
Country |
Parent |
892599 |
May 1992 |
|
Parent |
420842 |
Oct 1989 |
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