Annotation
Isotopic effects in high-$T_{c}$ systems are considered. For strong spin-phonon coupling, the calculated isotopic effect index is substantially lower than the classical index for low-$T_{c}$: superconductors. The isotopic effect indices of high-$T_{c}$: systems such as $\rm{La}_{2-x}\rm{Sr}_x\rm{CuO}_4$ and $\rm{YBa}_2 \rm{Cu}_3 \rm{O}_{7-y}$ are calculated from the dependence of the inverse exchange correlation length on the ion mass. This dependence can be obtained in the limit of maximum amplification of effective electron-phonon coupling by spin fluctuations of exchange nature. The theoretical estimates are compared with the experimental data.
© 2016 Publisher M.V.Lomonosov Moscow State University
Authors
A.V. Vedyaev, A.M. Savchenko, M.A. Savchenko, A.V. Stefanovich
Department of Magnetism, Faculty of Physics, Moscow State University, Leninskie Gory, Moscow, 119992, Russia
Department of Magnetism, Faculty of Physics, Moscow State University, Leninskie Gory, Moscow, 119992, Russia