Destruction of superconductivity and pseudogap closing in Bi$_2$Sr$_{2-x}$La$_x$CuO$_{6+\delta}$ by 58 T magnetic field

We measure the magnetic-field dependence of the c-axis resistivity $\rho_c(H)$ in a series of Bi$_2$Sr$_{2-x} $La$_x$CuO$_{6+\delta}$ (BSLCO) single crystals for a wide doping range using pulsed magnetic fields up to 58 T. [1] The behavior of $\rho_c(H)$ is examined with the recent determination of the upper critical field $H_{c2}$ by the Nernst effect measurements for the same BSLCO crystals. We find that the peak in $\rho_c(H)$ shows up at a field $H_p$ that is much lower than $H_{c2}$ and there is no discernable feature in $\rho_c(H)$ at $H_{c2}$. It is found that the doping dependence of $H_p$ essentially track that of $T_c$. Moreover, a new method is proposed for estimating the pseudogap closing field $H_{pg}$ from our BSLCO data, because we found that the method to estimate $H_{pg}$ in Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ [2] does not apply to our data. [1] S. Ono et al., cond-mat/0408603, To appear in PRB [2] T. Shibauchi et al. Phys. Rev. Lett. {\bf 86}, 5763 (2001).