In a ferromagnet which is coupled to a superconductor, a spin-singlet supercurrent can exist but will rapidly decay over a few nanometers [1, 2]. Enhancements to this proximity effect are predicted to occur in more exotic systems in which some inhomogeneous magnetism is present . In such systems, a supercurrent of electron pairs with a finite spin-projection (a spin-triplet supercurrent) may arise with a substantially longer coherence length than spin-singlet paired electrons in a ferromagnet. Evidence of a spin-triplet proximity effect in superconductor-ferromagnet systems has been indirectly observed by measuring supercurrents or substantial diminutions in the resistance across a range of complex magnetic barriers .
This presentation focuses on the properties of exotic Josephson junctions with various types of inhomogeneous magnetic barriers. In particular, reports of a substantially enhanced superconducting proximity effect in Fe/Cr/Fe  and Ho/Co/Ho  barriers will be discussed.
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