Theory of the d-density wave from a vertex model and its implications
Theory of the d-density wave from a vertex model and its implications
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顶点模型的 d 密度波理论及其含义
DOI：
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发表时间：
2002
期刊：
影响因子：
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通讯作者：
S. Chakravarty
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文献类型：
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作者：
S. Chakravarty
d-密度波的热无序，提出了高温超导体的赝能隙态的起源，建议是相同的统计力学模型称为六顶点模型。低温相由循环电流的交错序参量组成，而无序高温相是无序的幂律相。这种转变的一个特点是完全缺乏可观察到的比热异常在过渡。在更高的温度下也有一个跃迁，在这个温度下序参数的大小会崩溃。这些结果是由于经典的热涨落和完全无关的量子临界点在基态。量子力学的基态可以通过合并导致顶点之间的跃迁的过程来探索，使我们能够讨论基态中的量子相变以及在有限温度下量子临界性的影响，这与经典制度中的幂律波动不同。三角形晶格上的模型的推广，导致20个顶点的模型可能揭示在二维电子气中的金属-绝缘体转变的维格纳玻璃图片。幂律有序的高温相可能是通用的一类约束系统，其关系的量子二聚体模型的最新进展。
The thermal disordering of the d-density wave, proposed to be the origin of the pseudogap state of high-temperature superconductors, is suggested to be the same as that of the statistical mechanical model known as the six-vertex model. The low-temperature phase consists of a staggered order parameter of circulating currents, while the disordered high-temperature phase is a power-law phase with no order. A special feature of this transition is the complete lack of an observable specific heat anomaly at the transition. There is also a transition at a even higher temperature at which the magnitude of the order parameter collapses. These results are due to classical thermal fluctuations and are entirely unrelated to a quantum critical point in the ground state. The quantum-mechanical ground state can be explored by incorporating processes that causes transitions between the vertices, allowing us to discuss the quantum phase transition in the ground state as well as the effect of quantum criticality at a finite temperature as distinct from the power-law fluctuations in the classical regime. A generalization of the model on a triangular lattice that leads to a 20-vertex model may shed light on the Wigner glass picture of the metal-insulator transition in a two-dimensional electron gas. The power-law ordered high-temperature phase may be generic to a class of constrained systems, and its relation to recent advances in the quantum dimer models is noted.