Interlayer transport as a probe for the pseudogap in superconducting electron-doped cuprates

We report on the interlayer transport study in superconducting electron-doped Sm2 - x Cex CuO 4 - δ (0.14 ≲ x ≲ 0.16) crystals. Below a characteristic temperature T*, excess c-axis resistivity Δ ρc that decreases with magnetic fields has been observed in the normal state, which is similar to the features of the pseudogap state in Bi2 Sr2 CaCu2 O8 + y. We find that the magnitude of Δ ρc strongly correlates with the pseudogap closing field Hpg determined from the observed negative magnetoresistance, whose Zeeman energy scale agrees with T*. Our interlayer magneto-transport results provide the pseudogap phase diagrams essentially similar for both electron- and hole-doped cuprate superconductors. © 2006 Elsevier B.V. All rights reserved.