Charge transport along the c-axis in high-T_c cuprates

Using 61-T pulsed magnetic fields, the normal-state \rho_{ab} and \rho_{c} are measured in Bi-2201 system down to 0.66 K, and the coexistence of the “metallic” \rho_{ab} and the “semiconducting” \rho_{c}, usually called the charge confinement behavior, was confirmed to extend far below T_c. Recent measurement of the c-axis magnetoresistance under 16 T dc magnetic field in heavily underdoped Y-123 crystals revealed that the peculiar c-axis charge transport, and thus the charge confinement, is fundamentally related to the antiferromagnetic spin fluctuations.