2000/06/02 by T. Cren, T Cren, D. Roditchev +5
Physics and Astronomy · #Density of states #Local density of states #Nanometre #Physics of Superconductivity and Magnetism #Quantum tunnelling #Quasiparticle #Scanning tunneling microscope #Superconductivity #Superconductivity in MgB2 and Alloys #Topological Materials and Phenomena #cond-mat.supr-con
paper · pdf · doi:10.1209/epl/i2001-00232-4
4 page Letter with 3 figures (2 color figures)
arxiv created 2000/06/02 · openalex publication_date 2001/04/01 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
Using high-speed scanning tunneling spectroscopy (STS), we perform a full mapping of the quasiparticle density of states (DOS) in single crystals of Bi 2 − x Pb x Sr 2 CaCu 2 0 8 + δ . The measurements carried out at 5 K showed a complex spatial pattern of important variations of the local DOS on the nanometer scale. Superconducting areas, characterized by a well-pronounced superconducting gap, are coexisting with regions of a peakless gap structure which we attribute to the pseudogap. Within the large superconducting regions, the spectra reveal strong peak/dip/hump signatures, identical to the pristine Bi 2 Sr 2 CaCu 2 0 8 + δ case. On the contrary, in very small superconducting regions this fine structure is attenuated. Such a behavior of the local DOS suggests that the peak/dip/hump fine structure is not only a consequence of the superconducting state, but is also directly related to the scale of the phase coherence. The role of Bi-Pb substitutional disorder is discussed.