Quasiparticle mass enhancement approaching optimal doping in a high-Tc superconductor
Quasiparticle mass enhancement approaching optimal doping in a high-Tc superconductor
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DOI：
10.1126/science.aaa4990
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发表时间：
2015-04-17
期刊：
影响因子：
56.9
通讯作者：
Harrison, N.
中科院分区：
文献类型：
--
作者：
Ramshaw, B. J.;Sebastian, S. E.;Harrison, N.
在寻求具有更高转变温度（T-c）的超导体时，一个新兴的主题是有利于超导性的电子相互作用可以通过对称性破缺相的波动来增强。最近的实验表明，在高T-c铜酸盐中存在必要的对称性破缺相，但这种相对基态电子相互作用的影响仍然不清楚。我们使用超过90特斯拉的磁场访问的铜酸盐YBa 2Cu 3 O 6 + δ在很宽的掺杂范围内的底层金属状态，并观察到磁量子振荡，揭示了强增强的准粒子有效质量向最佳掺杂。这种质量增强的结果，从增加电子相互作用接近最佳掺杂，并建议在空穴掺杂的p（临界）接近0.18的量子临界点。
In the quest for superconductors with higher transition temperatures (T-c), one emerging motif is that electronic interactions favorable for superconductivity can be enhanced by fluctuations of a broken-symmetry phase. Recent experiments have suggested the existence of the requisite broken-symmetry phase in the high-T-c cuprates, but the impact of such a phase on the ground-state electronic interactions has remained unclear. We used magnetic fields exceeding 90 tesla to access the underlying metallic state of the cuprate YBa2Cu3O6+delta over a wide range of doping, and observed magnetic quantum oscillations that reveal a strong enhancement of the quasiparticle effective mass toward optimal doping. This mass enhancement results from increasing electronic interactions approaching optimal doping, and suggests a quantum critical point at a hole doping of p(crit) approximate to 0.18.