Pseudogap closing field of the overdoped Bi1.79Pb0.37Sr1.86CuO6+δ investigated by the out-of-plane resistivity in pulsed magnetic fields up to 40 T

We have measured the out-of-plane resistivity ρc of Pb-doped Bi2201 in strong magnetic fields up to 40 T. ρc measurements in 40 T have confirmed the existence of two kinds of pseudogap, namely the field-insensitive pseudogap PG1 and the sensitive PG2 which have been suggested from previous ρc measurements in 15 T. In the overdoped sample with the superconducting transition temperature Tc = 4 K, we have succeeded in the complete suppression of PG2. The temperature dependence of ρcin 40 T has indicated that the nonmetallic ρc(T) appears without PG2 on account of the existence of PG1 and/or the chargeconfinement in the ab-plane