Competing orders and quantum criticality in doped antiferromagnets
Competing orders and quantum criticality in doped antiferromagnets
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DOI：
10.1103/physrevb.62.6721
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发表时间：
2000-03
影响因子：
3.7
通讯作者：
M. Vojta;Ying Zhang;S. Sachdev
中科院分区：
文献类型：
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作者：
M. Vojta;Ying Zhang;S. Sachdev
我们使用了一些大N极限来研究破坏电磁空间群对称性的正方晶格掺杂反铁磁体基态之间的竞争。在我们发现的态中，有d-、{(S)^*+id)、{和${(d}_{{x}^{2}\ensuremath{-}{y}^{2}}{+id}_{\mathrm{xy}})$-wave超导体、维格纳晶体、空穴对维格纳晶体、轨道反铁磁体(或交错磁通态)，以及具有自旋-Peierls和键中心电荷条纹有序的态。在态与态之间的二阶量子相变附近，我们通过确定临界点的普适量子场论和计算费米子谱函数的有限温度、量子临界损耗，超越了大N极限。我们为Valla等人在${\mathrm{Bi}}_{2}{\mathrm{Sr}}_{2}{\mathrm{Ca}\mathrm{}\mathrm{Cu}}_{2}{\mathrm{O}}_{8+\ensuremath{\delta}}$上的光电子发射实验中最近观察到的量子临界行为确定了候选临界点。[科学285,2110(1999)]。其中包括d波超导体中电荷密度波的开始，或${d}_{{x}^{2}\ensuremath{-}{y}^{2}}{+id}_{\mathrm{xy}}$或${S}^{*}+id$配对的时间反转对称性破缺。不要求(虽然允许)掺杂铜酸盐中的稳定态不是d波超导体\char22{}，其他态只需在参数空间中的附近稳定即可。在有限的温度下，与这些附近态相关的涨落导致在布里渊区的节点处观察到的费米子衰减。由于序参数不需要满足任何特殊的可公度性条件，时间反转对称性破缺的情况很有吸引力。对于${d}_{{x}^{2}\ensuremath{-}{y}^{2}}{+id}_{\mathrm{xy}}$级涨落的情况，动量为$(\EnsureMath{\pi}，k)，$$(k，EnsureMath{\pi})$(具有$01~KL~\EnsureMath{\pi})的准粒子也很自然地没有非弹性阻尼。
We use a number of large-N limits to explore the competition between ground states of square lattice doped antiferromagnets which break electromagnetic $U(1),$ time-reversal, or square lattice space-group symmetries. Among the states we find are d-, ${(s}^{*}+id)\ensuremath{-},$ and ${(d}_{{x}^{2}\ensuremath{-}{y}^{2}}{+id}_{\mathrm{xy}})$-wave superconductors, Wigner crystals, Wigner crystals of hole pairs, orbital antiferromagnets (or staggered-flux states), and states with spin-Peierls and bond-centered charge stripe order. In the vicinity of second-order quantum phase transitions between the states, we go beyond the large-N limit by identifying the universal quantum field theories for the critical points, and computing the finite temperature, quantum critical damping of fermion spectral functions. We identify candidate critical points for the recently observed quantum critical behavior in photoemission experiments on ${\mathrm{Bi}}_{2}{\mathrm{Sr}}_{2}{\mathrm{Ca}\mathrm{}\mathrm{Cu}}_{2}{\mathrm{O}}_{8+\ensuremath{\delta}}$ by Valla et al. [Science 285, 2110 (1999)]. These involve onset of a charge-density wave, or of broken time-reversal symmetry with ${d}_{{x}^{2}\ensuremath{-}{y}^{2}}{+id}_{\mathrm{xy}}$ or ${s}^{*}+id$ pairing, in a d-wave superconductor. It is not required (although it is allowed) that the stable state in the doped cuprates be anything other than the d-wave superconductor\char22{}the other states need only be stable nearby in parameter space. At finite temperatures, fluctuations associated with these nearby states lead to the observed fermion damping in the vicinity of the nodal points in the Brillouin zone. The cases with broken time-reversal symmetry are appealing because the order parameter is not required to satisfy any special commensurability conditions. The observed absence of inelastic damping of quasiparticles with momenta $(\ensuremath{\pi},k),$ $(k,\ensuremath{\pi})$ (with $0l~kl~\ensuremath{\pi})$ also appears very naturally for the case of fluctuations to ${d}_{{x}^{2}\ensuremath{-}{y}^{2}}{+id}_{\mathrm{xy}}$ order.