Commensurate 4a0-period charge density modulations throughout the Bi2Sr2CaCu2O8+x pseudogap regime
Commensurate 4a0-period charge density modulations throughout the Bi2Sr2CaCu2O8+x pseudogap regime
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DOI：
10.1073/pnas.1614247113
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发表时间：
2016-11-08
影响因子：
11.1
通讯作者：
Kim, Eun-Ah
中科院分区：
文献类型：
--
作者：
Mesaros, Andrej;Fujita, Kazuhiro;Kim, Eun-Ah
基于强实空间(r空间)电子-电子相互作用的理论早已预言，在空穴掺杂的Cuprate Mott绝缘体(MI)中应该发生具有四个单元(4a(0))周期的单向电荷密度调制(CDM)。然而，在实验上，据报道，增加空穴密度p会导致CDM的传统定义的波矢Q(A)连续演化，似乎主要是由动量空间(k空间)效应驱动的。在这里，我们引入相分辨电子结构可视化来确定铜酸盐清洁发展机制的波矢。值得注意的是，这项技术揭示了在正则铜酸盐Bi2Sr2CaCu2O8的整个欠掺杂相图中，局域CDM波矢在垂直条Q(0)垂直条=2pi/4a(0)处的几乎与掺杂无关的锁定。这些观测具有重要的基本结果，因为它们与基于k空间(费米面)的铜酸盐CDM图是正交的，但与基于强耦合r空间的理论是一致的。我们的发现表明，正是后者为铜国清洁发展机制国家提供了内在的组织原则。
Theories based upon strong real space (r-space) electron-electron interactions have long predicted that unidirectional charge density modulations (CDMs) with four-unit-cell (4a(0)) periodicity should occur in the hole-doped cuprate Mott insulator (MI). Experimentally, however, increasing the hole density p is reported to cause the conventionally defined wavevector Q(A) of the CDM to evolve continuously as if driven primarily by momentum-space (k-space) effects. Here we introduce phase-resolved electronic structure visualization for determination of the cuprate CDM wavevector. Remarkably, this technique reveals a virtually doping-independent locking of the local CDM wavevector at vertical bar Q(0)vertical bar= 2 pi/4a(0) throughout the underdoped phase diagram of the canonical cuprate Bi2Sr2CaCu2O8. These observations have significant fundamental consequences because they are orthogonal to a k-space (Fermi-surface)-based picture of the cuprate CDMs but are consistent with strong-coupling r-space-based theories. Our findings imply that it is the latter that provides the intrinsic organizational principle for the cuprate CDM state.