On the Out-of-Plane Magnetotransport in YBa[sub 2]Cu[sub 3]O[sub y].

The out-of-plane resistivity, ρ[sub c], in a single-crystal YBa[sub 2]Cu[sub 3]O[sub y] follows the experimental law: ρ[sub c] = C[sub 1]ρ[sub ab] + C[sub 2]/T, where C[sub 1], C[sub 2] are the constants and ρ[sub ab] is in-plane resistivity in the concentration range 6.6 < y < 6.92 with the highest T[sub c], 90 K, occurring at y = 6.88 and in the temperature range T[sub c] < T < room temperature. This behavior is microscopically explained under the assumption that the charge carriers are a mixture of "electrons", "holes", and ± pairons. The second term C[sub 2]/T arises from the quantum tunneling between copper planes of the — pairons, moving with a linear dispersion relation, and the first term C[sub 1]ρ[sub ab] from the in-plane currents due to the "holes" and + pairons. [ABSTRACT FROM AUTHOR]