Ice: A strongly correlated proton system
Ice: A strongly correlated proton system
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DOI：
10.1103/physrevb.74.024302
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发表时间：
2006-07-01
影响因子：
3.7
通讯作者：
Fradkin, Eduardo
中科院分区：
文献类型：
--
作者：
Castro Neto, A. H.;Pujol, P.;Fradkin, Eduardo
我们讨论了质子在氢键材料中的运动问题，特别关注冰。我们表明，过去提出的用于研究冰的现象学模型可以根据与用于研究莫特-哈伯德绝缘体的物理密切相关的微观模型进行重铸。我们讨论了1/4填充冰（中性冰）的顺磁相位的物理性质，以及它与横向场Ising模型和二维和三维规范理论的映射。我们发现H3+O和HO-离子既可以处于受限相，也可以处于限定相。我们得到了问题的相图作为温度T和质子跳跃能量T的函数，发现有两个相：一个是由量子涨落引起的无序有序机制产生的有序绝缘相，另一个是无序非相干金属相（或等离子体）。我们还讨论了由晶格振动（声子）引入的质子运动中的退相干问题及其对相图的影响。最后，我们提出在实验中观察到的掺杂冰从冰Ih到冰XI的转变是我们相图的限制-定义转变。
We discuss the problem of proton motion in hydrogen bond materials with special focus on ice. We show that phenomenological models proposed in the past for the study of ice can be recast in terms of microscopic models in close relationship to the ones used to study the physics of Mott-Hubbard insulators. We discuss the physics of the paramagnetic phase of ice at 1/4 filling (neutral ice) and its mapping to a transverse field Ising model and also to a gauge theory in two and three dimensions. We show that H3+O and HO- ions can be either in a confined or deconfined phase. We obtain the phase diagram of the problem as a function of temperature T and proton hopping energy t and find that there are two phases: an ordered insulating phase which results from an order-by-disorder mechanism induced by quantum fluctuations, and a disordered incoherent metallic phase (or plasma). We also discuss the problem of decoherence in the proton motion introduced by the lattice vibrations (phonons) and its effect on the phase diagram. Finally, we suggest that the transition from ice Ih to ice XI observed experimentally in doped ice is the confining-deconfining transition of our phase diagram.