Holographic methods for the theory of High-Tc Superconductors

高温超导体理论的全息方法

• 批准号: EP/I02669X/1
• 负责人: Sergey Slizovskiy
• 金额: $ 19.6万
• 依托单位: Loughborough University
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2012
• 资助国家: 英国
• 起止时间: 2012 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FI02669X%2F1
• 关键词: Holographic; methods; theory; Tc; Superconductors

High-temperature superconducting (HTSC) materials have been a dream of scientists since 1911, when superconductivity was first observed by Kamerlingh Onnes. In 1986, after the pioneering work of Bednorz and Mueller, it was soon discovered that some cuprate-perovskite ceramic materials have critical temperatures, Tc, above 90 Kelvin (183 degrees C). These high-Tc superconductors renewed interest in the topic because of the prospects for improvement and potential room-temperature superconductivity.HTSCs have attracted great interest not only for their obvious potential applications in electronics, high-power magnets and high-precision detectors, but also for their scientific complexity. Despite 25 years of intensive development, the origin of HTSC and various thermodynamic phases arising in these materials are still not clear. Of fundamental importance is that all these systems are characterised by strong electron correlations, where conventional methods used in Condensed Matter Physics are not functional. As it has become clear recently, the unusual properties of these materials are governed by the presence of a quantum critical point at zero temperature (S.Sachdev 2008, D.M.Broun 2008).The purpose of the proposed research is to apply novel theoretical methods to be able to describe such strongly-correlated electron systems: HTSCs as well as two-dimensional electron gas and heavy-fermion compounds. This research is interdisciplinary: it requires knowledge of both condensed matter theory methods, quantum field theory and string theory.These novel methods are commonly called holography'' (J.Maldacena 1997, A.Polyakov 1998, E.Witten 1998): these are motivated by string theory and are applicable to the region of the phase diagram near the quantum critical point. Holographic methods are capable of describing the unusual properties of materials in terms of gravity theory in higher-dimensional space-time, where symmetries of the quantum critical point are realised geometrically. Holographic methods can be extended to non-zero temperatures by considering gravity solutions with black holes; and many real-time dynamical properties of the material, such as conductivity and heat transport may be computed. Thus, there exists a fascinating and previously unexpected opportunity to connect superconductors with black hole physics. The holographic framework has recently become very popular among string theorists, but the connection of these models with underlying lattice physics has not yet been established on the microscopic level. Studying this connection and establishing explicit relations between known microscopic lattice models and holographic models is the central objective of the research. This is expected to lead to a brand new framework for describing high-temperature superconductors and other materials with exotic properties. It may even lead to the prediction of new phases of matter.

自1911年卡默林昂尼斯首次观察到超导性以来，高温超导材料一直是科学家们的梦想。1986年，在Bednorz和Mueller的开创性工作之后，人们很快发现一些铜钙钛矿陶瓷材料的临界温度Tc高于90开尔文（183摄氏度）。由于这些高tc超导体的改进前景和潜在的室温超导性，重新引起了人们对该主题的兴趣。高温超导材料吸引了人们的极大兴趣，不仅因为它们在电子、大功率磁铁和高精度探测器方面的明显潜在应用，而且因为它们的科学复杂性。尽管经过了25年的深入研究，HTSC的起源和这些材料中出现的各种热力学相仍然不清楚。最重要的是，所有这些系统都具有强电子相关性，而在凝聚态物理中使用的传统方法不起作用。正如最近已经清楚的那样，这些材料的不寻常特性是由零温度下量子临界点的存在所控制的（S.Sachdev 2008, d.m.b rown 2008）。提出的研究目的是应用新的理论方法来描述这种强相关的电子系统：htsc以及二维电子气体和重费米子化合物。这项研究是跨学科的：它需要凝聚态理论方法，量子场论和弦理论的知识。这些新方法通常被称为全息”（J.Maldacena 1997， A.Polyakov 1998， E.Witten 1998）：这些方法是由弦理论驱动的，适用于量子临界点附近的相图区域。全息方法能够根据高维时空中的引力理论描述材料的不寻常特性，在高维时空中，量子临界点的对称性是几何上实现的。通过考虑黑洞的引力解，全息方法可以扩展到非零温度；并且可以计算材料的许多实时动态特性，如电导率和热传递。因此，将超导体与黑洞物理联系起来是一个令人着迷的、以前意想不到的机会。全息框架最近在弦理论家中非常流行，但是这些模型与底层晶格物理的联系尚未在微观层面上建立起来。研究这种联系并建立已知微观晶格模型和全息模型之间的明确关系是本研究的中心目标。这有望为描述高温超导体和其他具有奇异性质的材料提供一个全新的框架。它甚至可能导致对物质新相的预测。

项目成果

Bound states of charges on top of graphene in a magnetic field

• DOI: 10.1103/physrevb.92.195426
• 发表时间: 2015-05
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: S. Slizovskiy

Nematic phase in a two-dimensional Hubbard model at weak coupling and finite temperature

• DOI: 10.1103/physrevb.98.075126
• 发表时间: 2018-03
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: S. Slizovskiy;P. Rodriguez-Lopez;J. Betouras

Magnetic fluctuations and specific heat in Na(x)CoO2 near a Lifshitz transition.

• DOI: 10.1103/physrevlett.114.066403
• 发表时间: 2014-09
• 期刊: Physical review letters
• 影响因子: 8.6
• 作者: S. Slizovskiy;A. Chubukov;J. Betouras

Effect of paramagnetic fluctuations on a Fermi-surface topological transition in two dimensions

顺磁涨落对二维费米表面拓扑转变的影响

• DOI: 10.1103/physrevb.90.165110
• 发表时间: 2014
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: Slizovskiy S

Charging of graphene by a magnetic field and the mechanical effect of magnetic oscillations.

磁场对石墨烯充电和磁振荡的机械效应。

• DOI: 10.1088/0953-8984/25/49/496007
• 发表时间: 2013
• 期刊: an Institute of Physics journal
• 作者: Slizovskiy S