The in-plane resistivity ρa(T) and the out-of-plane resistivity ρc(T) have been systematically measured for Bi2Sr2CaCu2O8+δ single crystals with their oxygen contents precisely controlled. In the underdoped region, deviation from T-linear in-plane resistivity, which evidences the opening of the "spin gap," is clearly observed, while the out-of-plane resistivity is well reproduced by the activation-type phenomenological formula ρc(T) = (a/T)exp(Δ/T) + c. In contrast to the YBa2Cu3Cu3O7-δ system, we find that the onset of the semiconducting ρc(T) does not coincide with the opening of the spin gap seen in the ρa(T) in this Bi2Sr2CaCu2O8+δ system.
|Number of pages||4|
|Journal||Physical Review Letters|
|Publication status||Published - 1997|
ASJC Scopus subject areas
- Physics and Astronomy(all)