Abstract
We show that the spin chain/ladder compound is an insulator with hopping transport along the chains. In the temperature range 35–280 K, dc conductivity follows Mott’s law of variable-range hopping conduction; the frequency dependence has the form where The conduction mechanism changes from variable-range hopping to nearest-neighbor hopping around The chain array thus behaves as a one-dimensional disordered system. Disorder is due to random structural distortions of chains induced by irregular coordination of the La/Sr/Ca ions.
- Received 13 December 2002
DOI:https://doi.org/10.1103/PhysRevB.67.184521
©2003 American Physical Society