Evidence for ubiquitous strong electron-phonon coupling in high-temperature superconductors
Evidence for ubiquitous strong electron-phonon coupling in high-temperature superconductors
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DOI：
10.1038/35087518
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发表时间：
2001-08-02
期刊：
影响因子：
64.8
通讯作者：
Shen, ZX
中科院分区：
文献类型：
--
作者：
Lanzara, A;Bogdanov, PV;Shen, ZX
电子和声子之间的耦合（晶格振动）驱动了传统超导性的电子对的形成（1）。在高转变温度超导体的电子动力学中缺乏电子-声子耦合的直接证据，这促使人们深入研究替代机制。电子与声子的耦合将导致其速度和散射率在声子能量附近的突变。在这里，我们使用角分辨光电子能谱探测电子动力学速度和散射率三个不同的家庭的氧化铜超导体。在所有这些材料中，我们都看到电子速度在50-80 meV处发生突变，除了与氧原子运动相关的声子耦合之外，我们无法用任何已知的过程来解释。这表明电子-声子耦合强烈影响高温超导体中的电子动力学，因此必须包含在任何超导的微观理论中。
Coupling between electrons and phonons (lattice vibrations) drives the formation of the electron pairs responsible for conventional superconductivity(1). The lack of direct evidence for electron-phonon coupling in the electron dynamics of the high-transition-temperature superconductors has driven an intensive search for an alternative mechanism. A coupling of an electron with a phonon would result in an abrupt change of its velocity and scattering rate near the phonon energy. Here we use angle-resolved photoemission spectroscopy to probe electron dynamics-velocity and scattering rate-for three different families of copper oxide superconductors. We see in all of these materials an abrupt change of electron velocity at 50-80 meV, which we cannot explain by any known process other than to invoke coupling with the phonons associated with the movement of the oxygen atoms. This suggests that electron-phonon coupling strongly influences the electron dynamics in the high-temperature superconductors, and must therefore be included in any microscopic theory of superconductivity.