Electron transport in hybrid superconductor heterostructures with manganite interlayers

• Hybrid herostructures comprising an YBa(2)Cu(3)O (x) (YBCO) high-temperature superconductor (HTS) layer and Nb/Au low-temperature superconductor (LTS) bilayer (with critical HTS and LTS temperatures T (c) and T'(c), respectively), separated by a thin (d (M) = 5-20 nm) interlayer of LaMnO(3), La(0.7)Ca(0.3)MnO(3), or La(0.7)Sr(0.3)MnO(3) manganite have been studied. The electric resistance and magnetic properties of individual (evaporated directly onto the substrate) manganite films and related hybrid herostructures have been measured. Based on quasi-classical equations, analytical expressions for the conductivity of herostructures at T a parts per thousand currency sign T'(c) are obtained in the case of a low-transparency superconductor/manganite interface. It is established that the conductivity of heterostructures is determined by the proximity effect (related to the penetration of a condensate wavefunction from the Nb/Au bilayer to manganite) and depends strongly on interface transparency. At low temperatures (T a parts per thousand(a) T (c)'), the conductivity peaks are found at voltages determined by the exchange field of the manganite interlayer. At T (c)'

Subject headings

NATURVETENSKAP  -- Fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences (hsv//eng)

Keyword

ferromagnet structures

magnetizations

interfaces

junctions

layers

Publication and Content Type

art (subject category)

ref (subject category)