Competing orders in low dimensional organic superconductors

本研究计划将主要集中于基于弱耦合重整化群（RG）理论的理论工具的开发和应用，这一计划基本上是由准一维有机超导体的实验所激发的。尽管它们的分子结构复杂，但这些相关系统作为一种简单的范例，在反铁磁性和非常规超导性之间表现出密切的接近。我们将利用RG方法的适用性来研究这种材料的压力-温度相图中磁性自旋密度波相附近与超导性相关的量子临界性质。RG方法将扩展到高阶，以研究围绕量子临界的集体激发及其对超导前金属相准粒子态的影响。将特别强调准粒子激发的性质，它们的光谱特征进入输运量的行为，其观察到的异常行为自从在非常规超导体中发现以来一直是一个持久的问题，包括质子、铜酸盐和重费米子系统。

This research program will be mainly focused on the development and application of theoretical tools grounded on the weak coupling renormalization group (RG) theory, a plan essentially stimulated by experiments that are carried out on quasi-one-dimensional organic superconductors. In spite of their complex molecular structure, these correlated systems stand out as a paradigm of simplicity to exhibit a close proximity between antiferromagnetism and unconventional superconductivity. We shall exploit the aptness of the RG method to study the nature of quantum criticality associated with superconductivity in the close vicinity of a magnetic spin-density wave phase in the Pressure-Temperature phase diagram of such materials. The RG method will be extended to high order to investigate the collective excitations surrounding quantum criticality and their influence on quasi-particles states of the metallic phase that precedes superconductivity. Particular emphasis will be put on the nature of quasi-particle excitations, their spectral features that enter in the behavior of transport quantities, whose observed anomalous behaviors have remained an enduring question since their discovery in unconventional superconductors including pnictides, cuprates and heavy-fermion systems.