Phonon-Assisted Electron Hopping Conduction in the Uranium Doped One-Dimensional Antiferromagnet Ca2CuO3

Abstract

The authors studied the conduction mechanism in an uranium doped low dimensional magnetic system Ca2CuO3. This system exhibits the S=1/2 quasi 1D antiferromagnetic chains of -Cu-O- with strong magnetic coupling, and demonstrates continuous semiconductor-like behavior with constant covalent insulator character. This paper identifies the conduction is due to thermally activated phonon-assisted electron hopping between dopant uranium sites. The parameter á, the characteristic for hopping probability, was determined to be 0.18 Å−1. This value manifests a relatively stronger hopping probability for Ca2CuO3 as compared with other uranium doped ceramics.