Intrinsic tunneling spectra of Bi2(Sr(2-x)Lax)CuO(6+delta)

Phys Rev Lett. 2003 Apr 11;90(14):147005. doi: 10.1103/PhysRevLett.90.147005. Epub 2003 Apr 11.

Abstract

We have measured intrinsic-tunneling spectra of a single CuO-layer La-doped Bi2(Sr(2-x)Lax)CuO(6+delta) (Bi2201-Lax). Despite a difference of a factor of 3 in the optimal superconducting critical temperatures for Bi2201-La0.4 and Bi2212 (32 and 95 K, respectively) and different spectral energy scales, we find that the pseudogap vanishes at a similar characteristic temperature T* approximately 230-300 K for both compounds. We find also that, in Bi2201-Lax, pseudogap humps are seen as sharp peaks and, in fact, even dominate the intrinsic spectra.