ISSN:
1572-9605
Keywords:
Tc Amplification
;
Superlattice
;
Quantum wires
;
Stripes
Source:
Springer Online Journal Archives 1860-2000
Topics:
Electrical Engineering, Measurement and Control Technology
,
Physics
Notes:
Abstract Here we report experimental evidence that the high Tc superconductivity in a cuprate perovskite occurs in a superlattice of Josephson coupled quantum wires. We show that this particular heterostructure provides the physical mechanism raising Tc from the low temperature range Tc〈23K to the high temperature range 30K〈Tc〈150K by amplification of the critical temperature of the homogeneous CuO2 plane by a factor ∼10. The structure of the high Tc superconducting CuO2 plane in Bi2Sr2CaCu2O8+y (Bi2212) at the mesoscopic level (10–100 Å) has been determined. The superconducting plane is decorated by a plurality of parallel superconducting stripes of width L defined by the domain walls formed by stripes of width W characterized by a short Cu-O(apical) distance and large tilting ∼ 110° of the distorted square pyramids. We have measured the width of the domain walls W=11±1 Å and of the stripes L=14±1 Å. The critical parameters raising Tc are: 1) the Fermi level is near the bottom of the second subband of the stripes, with k2y=2π/L, formed by the quantum size effect and 2) W is of the order of the superconducting coherence length ξ0.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00727421
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