High-transition-temperature superconductivity in the absence of the magnetic-resonance mode

Article

关键词: T-C;    NEUTRON-SCATTERING;    SPIN FLUCTUATIONS;    PSEUDOGAP;    STATE;    EXCITATION;    INPLANE;    PEAK;   

DOI  :  10.1038/nature02347

来源: SCIE

【 摘 要 】

The fundamental mechanism that gives rise to high-transition-temperature (high-T-c) superconductivity in the copper oxide materials has been debated since the discovery of the phenomenon. Recent work has focused on a sharp 'kink' in the kinetic energy spectra of the electrons as a possible signature of the force that creates the superconducting state(1-14). The kink has been related to a magnetic resonance(13,15-17) and also to phonons(18). Here we report that infrared spectra of Bi2Sr2CaCu2O8+delta (Bi-2212), shows that this sharp feature can be separated from a broad background and, interestingly, weakens with doping before disappearing completely at a critical doping level of 0.23 holes per copper atom. Superconductivity is still strong in terms of the transition temperature at this doping (T-c approximate to 55 K), so our results rule out both the magnetic resonance peak and phonons as the principal cause of high-T-c superconductivity. The broad background, on the other hand, is a universal property of the copper-oxygen plane and provides a good candidate signature of the 'glue' that binds the electrons.

【 授权许可】

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