Modulated microwave absorption of YBa₂Cu₃O_7-δ thin films on LiNbO₃

The temperature dependence of the modulated microwave absorption of YBa2Cu3O7-δ thin films is shown to exhibit a maximum near Tc where the same signals for ceramic samples go to zero. The maximum is very similar to that usually found in the imaginary part of the susceptibility measured at low frequencies due to the intragranular fluxons. © 1989.