Microwave collective transport in single-crystal Eu2CuO

We measured the complex conductivity of single crystals of Eu2CuO4 from 3 to 15 GHz and observed collective transport with a sample-independent spectral weight. An unusual activated temperature dependence for the spectral weight, and anomalous temperature dependence of the Eu Mossbauer line, indicate magnetic effects well above the Néel temperature. The collective transport is similar to that observed in (TMTSF)2PF6 where TMSF denotes tetramethyltetrathiofulvalene and where charged, massive solitons are the suspected source of the transport. © 1988 The American Physical Society