Doping Dependent Evolution of the Fermi Surface and Competing Ordering Phenomena in Superconduction Cuprates

详细了解费米表面的尺寸和拓扑结构及其随掺杂的演变是理解铜超导体物理学的关键因素。到目前为止，费米表面上的信息大多来自于表面敏感的ARPES实验，受到表面极化和自掺杂效应的影响。幸运的是，单晶的质量已经提高到一个水平，允许首次观察磁性量子振荡（Shubnikovde Haas和de Haas-van Alphen效应）。这为一种全新的实验类型开辟了可能性，提供了关于铜超导体体电子特性的高度期望的信息。本文的主要目的是利用磁量子振荡的方法，详细系统地研究各种铜超导体费米表面的尺寸和拓扑结构及其随掺杂的演变。我们的实验是基于超净单晶的，最近已经成功地证明了磁量子振荡的观察。它们有望为铜超导体的超导起源和竞争有序现象提供新的有价值的信息。

The detailed knowledge of the size and topology of the Fermi surface as well as its evolution with doping is a key ingredient for understanding the physics of the cuprate superconductors. So far, information on the Fermi surface has been mostly obtained from surface-sensitive ARPES experiments, suffering from surface polarization and self-doping effects. Fortunately, the quality of single crystals has been improved to a level, allowing for the first time for the observation of magnetic quantum oscillations (Shubnikovde Haas and de Haas-van Alphen effect). This opened up the possibility for a completely new class of experiments, providing the highly desired information on the bulk electronic properties of cuprate superconductors. The key goal of this proposal is the detailed and systematic study of the size and topology of the Fermi surface of various cuprate superconductors as well as its evolution with doping by means of magnetic quantum oscillations. Our experiments are based on ultra-clean single crystals, for which the observation of magnetic quantum oscillations has been successfully demonstrated very recently. They are expected to provide new and valuable information on the origin of superconductivity and competing ordering phenomena in the cuprate superconductors.