A smoking gun signature for a first-order phase transition with negative speed of sound squared $c_s^2$ is the occurrence of a spinodal instability. In the gauge/gravity duality it corresponds to a Gregory-Laflamme type instability, which can be numerically simulated as the evolution of unstable planar black branes. Making use of holography its dynamics is studied far from and near a critical point with the following results. Near a critical point the interface between cold and hot stable phases, given by its width and surface tension, is found to feature a wider phase separation and a smaller surface tension. Far away from a critical point the formation time of the spinodal instability is reduced. Across softer and harder phase transitions, it is demonstrated that mergers of equilibrated peaks and unstable plateaux lead to the preferred final single phase separated solution. Finally, a new atypical setup with dissipation of a peak into a plateau is discovered. In order to distinguish the inhomogeneous states I propose a new criterium based on the maximum of the transverse pressure at the interface which encodes phase-mixed peaks versus fully phase separated plateaux.
Holographic antiferromganetic quantum criticality and AdS$_2$ scaling limit
本文对磁场诱导的反铁磁量子相变（QPT）和量子临界点（QCP）附近的临界性进行了数值研究。本文证明了在这个全息模型中QPT的性质是由一个与红外区突现的AdS $_2$的CFT对偶决定的，从而证实了对偶边界理论是一个具有动力学指数$z=2$的强耦合理论，并出现了对数修正.并与Hertz模型在上临界维数下求解RG方程的结果以及高温超导体Er $_{2-2x}$ Y $_{2x}$ Ti $_2$ O $_7$和BiCoPO $_5$的实验数据进行了比较.
Universally Diverging Grüneisen Ratio of Holographic Quantum Criticality
Institute of Theoretical Physics, Chinese Academy of Sciences（中国科学院理论物理研究所）；School of Physical Sciences, University of Chinese Academy of Sciences（中国科学院大学物理科学学院）；School of Fundamental Physics and Mathematical Sciences, Hangzhou Institute for Advanced Study, UCAS（杭州高等研究院基础物理与数学学院）
$P$--$V$ criticality, Joule--Thomson expansion, and holographic heat engine of charged Hayward-AdS black holes with a cloud of strings and perfect fluid dark matter
Al-Hussein Bin Talal University（侯赛因·本·塔拉勒大学）；The Assam Royal Global University（阿萨姆皇家全球大学）；Eastern Mediterranean University（东地中海大学）
Quantum criticality and mixed-state entanglement in holographic superconductor--insulator transitions
Department of Physics and Siyuan Laboratory, Jinan University（暨南大学物理系思源实验室）；School of Physics and Astronomy, Beijing Normal University（北京师范大学物理学院）；Institute of High Energy Physics, Chinese Academy of Sciences（中国科学院高能物理研究所）；School of Physics, University of Chinese Academy of Sciences（中国科学院大学物理学院）
Quantum Criticality and Holographic Superconductors in M-theory
本文给出了任意7维Sasaki-Einstein空间（SE_7）上D=11的超引力到D=4的包含度规、规范场、复标量场和实标量场的理论的一致Kaluza-Klein截断.我们使用这个D=4的理论来构造各种黑洞解，这些解描述了d=3的CFTs的热力学性质，这些CFTs对偶于偏斜的AdS_4 X SE_7解。我们发现，这些CFTs有一个丰富的相图，包括全息超导，一般来说，破宇称和时间反演不变性。在零温度下，超导溶液是带电畴壁，在远红外具有普遍的出射共形对称性。
We study the hololgraphic dual of the extended thermodynamics of spherically symmetric, charged AdS black holes in the context of the AdS/CFT correspondence. The gravitational thermodynamics of AdS black holes can be extended by allowing for variations of the cosmological constant and Newton's constant. In the dual CFT this corresponds to including the central charge $C$ and its chemical potential $μ$ as a new pair of conjugate thermodynamic variables, in addition to the standard pairs: temperature vs. entropy $(T,S)$, electric potential vs. charge $(\tilde Φ, \tilde Q)$ and field theory press…
Holographic CFT phase transitions and criticality for charged Gauss-Bonnet AdS black holes in the ensemble at fixed $(C, \mathcal{V}, \tilde{Q}, \tilde{\mathcal{A}})$
School of Fundamental Physics and Mathematical Sciences, Hangzhou Institute for Advanced Study, UCAS（杭州高等研究院基础物理与数学学院，UCAS）；Institute of Theoretical Physics, Chinese Academy of Sciences（中国科学院理论物理研究所）；University of Chinese Academy of Sciences（中国科学院大学）
An analytic approach for holographic entanglement entropy at (quantum) criticality
Fergusson College (Autonomous), Savitribai Phule Pune University（萨维特里拜·普莱·浦那大学费古森学院（自治））；Asia Pacific Center for Theoretical Physics（亚太理论物理中心）；Pohang University of Science and Technology（韩国科学技术院）；Institute of Theoretical Physics, Chinese Academy of Sciences（中国科学院理论物理研究所）
We study the competition between the p-wave and the p+ip superfluid solutions in a holographic model with applied magnetic field intensity $H$. We find that when $H$ is turned on, both the grand potential and the critical temperature of the p+ip solution are shifted, while the p-wave solution is only slightly affected. Combining the effect of $H$ and back reaction parameter b, we build $H-T$ phase diagrams with a slit region of p+ip phase. The zero (or finite) value of $H$ at the starting point of the slit region is related to second (or first) order of the p-wave phase transition at zero magn…
Capturing the interplay between electronic correlations and many-particle entanglement requires a unified framework for Hamiltonian and eigenbasis renormalization. In this work, we apply the unitary renormalization group (URG) scheme developed in a companion work (Ref.[1]) to the study of two archetypal models of stongly correlated lattice electrons, one with translation invariance and one without. We obtain detailed insight into the emergence of various gapless and gapped phases of quantum electronic matter by computing effective Hamiltonians as well as entanglement signatures through their r…
Understanding electrical transport in strange metals, including the seeming universality of Planckian $T$-linear resistivity, remains a longstanding challenge in condensed matter physics. We propose that local imaging techniques, such as nitrogen vacancy center magnetometry, can locally identify signatures of quantum critical response which are invisible in measurements of a bulk electrical resistivity. As an illustrative example, we use a minimal holographic model for a strange metal in two spatial dimensions to predict how electrical current will flow in regimes dominated by quantum critical…
