Superconductor flux pinning without columnar defects
View Patent ↗There is a superconducting article that includes a superconducting film comprising a substrate, one or more buffer layers, and a high temperature superconducting (HTS) layer. The superconducting layer may be comprised of the chemical composition REBa 2 Cu 3 O 7−x , where RE is one or more rare earth elements, for example: Y, La, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu. The superconductor layer is produced using Photo-Assisted Metal Organic Chemical Vapor Deposition (PAMOCVD) and contains non-superconducting nanoparticles. The nanoparticles are substantially provided in the a-b plane and naturally oriented. The non-superconducting nanoparticles provide flux pinning centers that improve the critical current properties of the superconducting film.
1. A thin film composite high-temperature superconducting article comprising:
a substrate;
a buffer layer; and
a high-temperature superconducting layer,
wherein the high-temperature superconducting layer further comprises non-superconducting material distributed along the a-b plane coplanar with the superconducting layer and without distribution along the c-axis such that the non-superconducting material lacks a substantial vertically oriented component.
2. The superconducting article of claim 1 , wherein the non-superconducting material is randomly distributed in the a-b plane of the superconducting layer.
3. The superconducting article of claim 1 , wherein the non-superconducting material is comprised of nano-particulates.
4. The superconducting article of claim 1 , wherein the non-superconducting material is non-crystalline.
5. The superconducting article of claim 1 , wherein the non-superconducting material is comprised of RE 2 O 3 where RE includes one or more of the following elements: Y, La, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb or Lu.
6. The superconducting article of claim 1 , wherein the non-superconducting material is comprised of BaMO 3 where M includes one or more of the following elements: Ti, Zr, Al, Hf, Ir, Sn, Nb, Mo, Ta, Ce, and V.
7. The superconducting article of claim 1 , wherein the buffer layer and high-temperature superconducting layers are selected to ensure a lattice mismatch between the two layers.
8. A method of forming a high-temperature superconductor, the method comprising
providing a substrate;
depositing a buffer layer upon the substrate;
depositing a high-temperature superconducting layer upon the buffer layer; and
co-depositing a non-superconducting material distributed preferentially along the a-b plane coplanar with the superconducting layer, wherein the non-superconducting material is randomly distributed and lacks a substantial vertically oriented component.
9. The method of claim 8 , wherein the non-superconducting material is comprised of RE 2 O 3 where RE includes or more of the following elements: Y, La, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb or Lu.
10. The method of claim 8 , wherein the non-superconducting material is comprised of BaMO 3 where M includes one or more of the following elements: Ti, Zr, Al, Hf, Ir, Sn, Nb, Mo, Ta, Ce, and V.
11. The method of claim 8 , wherein the non-superconducting material is deposited by introducing an atomic excess of RE during co-deposition with the superconducting layer.
12. The method of claim 8 , wherein the non-superconducting material is deposited by introducing an atomic excess of Ba and new element M where M includes one or more of the following elements: Ti, Zr, Al, Hf, Ir, Sn, Nb, Mo, Ta, Ce, and V during co-deposition with the superconducting layer.
13. The method of claim 8 , wherein the buffer layer, high-temperature superconducting layer, and non-superconducting material are deposited by photo-assisted MOCVD (PAMOCVD).
14. The method of claim 13 , further wherein the high-temperature superconducting layer growth rate is 1.0 μm/min or greater.
15. A thin film composite high-temperature superconducting article comprising:
a substrate;
a buffer layer;
a high-temperature superconducting layer;
non-superconducting material distributed preferentially along the a-b plane coplanar with the superconducting layer and without distribution along the c-axis such that the non-superconducting material lacks a substantial vertically oriented component; and
a lift factor at 4K, 20T (Ic (4K, 20T)/Ic (77K, self-field)) of 2 or greater.
16. The superconducting article of claim 15 , wherein the non-superconducting material is randomly dispersed in the a-b plane of the superconducting layer.
17. The superconducting article of claim 15 , wherein the non-superconducting material distributed preferentially along the a-b plane coplanar with the superconducting layer lacks a substantial vertically oriented component.
18. The superconducting article of claim 15 , wherein the lift factor is 3 or greater.
19. The superconducting article of claim 15 , wherein the superconductor further comprises a critical current (Ic) of 450 A/cm-width or higher at 4K and 20T.