Giant oscillations of coupling strength in Mo/Si multilayers with constant semiconductor thickness

Abstract

We report the observation of anisotropy ratio $\ensuremath{\gamma}$ and interlayer-coupling-strength oscillations with variation of metal-layer thickness in Mo/Si multilayer series with constant Si-layer thickness. These oscillations correlate with previously found oscillations of ${T}_{c},$ ${R}_{300}{/R}_{n},$ and ${\mathrm{dH}}_{c\ensuremath{\perp}}/dT$. The giant amplitude of $\ensuremath{\gamma}$ oscillations makes one believe that all oscillation effects are due to the variation of the Josephson coupling. The possible origin of these unusual effects is discussed.