Giant absorption of an rf electromagnetic field in conducting ceramics
Shcherbakov A. S. , Katsnel'son M. I. , Trefilov A. V., Sorokin N. L., Valiulin E. G., Petrov A. N.
A giant absorption of power from an rf field (v~ 1 GHz) has been observed in La2Cu04 and in systems with a metallic conductivity, La2 _x Srx Cu04 _ y and YBa2Cu307 + δ. The observed effects are interpreted as ferroelectric anomalies at finite frequencies, caused by the low-frequency lattice dynamics. A phenomenological model is offered to describe the coexistence of ferroelectric anomalies and a metallic conductivity.