Qiyuan Pan

Holographic superconductors with Power-Maxwell field

A bstractWith the Sturm-Liouville analytical and numerical methods, we investigate the behaviors of the holographic superconductors by introducing a complex charged scalar field coupled with a Power-Maxwell field in the background of d-dimensional Schwarzschild AdS black hole. We note that the Power-Maxwell field takes the special asymptotical solution near boundary which is different from all known cases. We find that the larger power parameter q for the Power-Maxwell field makes it harder for the scalar hair to be condensated. We also find that, for different q, the critical exponent of the system is still 1/2, which seems to be an universal property for various nonlinear electrodynamics if the scalar field takes the form of this paper.

Analytical investigation of the phase transition between holographic insulator and superconductor in Gauss-Bonnet gravity

A bstractWe employ the variational method for the Sturm-Liouville eigenvalue problem to analytically study the phase transition between the holographic insulator and supercon- ductor in the Gauss-Bonnet gravity. By investigating the s-wave and p-wave holographic insulator/superconductor models, we find that this analytic method is more effective to obtain the analytic results on the condensation and the critical phenomena in the AdS soliton background in Gauss-Bonnet gravity. Our analytic result can be used to back up the numerical computations in the AdS soliton with Gauss-Bonnet correction.

Holographic insulator/superconductor phase transition with Weyl corrections

Abstract We analytically investigate the phase transition between the holographic insulator and superconductor with Weyl corrections by using the variational method for the Sturm–Liouville eigenvalue problem. We find that similar to the curvature corrections, in p-wave model, the higher Weyl couplings make the insulator/superconductor phase transition harder to occur. However, in s-wave case the Weyl corrections do not influence the critical chemical potential, which is in contrast to the effect caused by the curvature corrections. Moreover, we observe that the Weyl corrections will not affect the critical phenomena and the critical exponent of the system always takes the mean-field value in both models. Our analytic results are found to be in good agreement with the numerical findings.

Analytical study on holographic superconductors with backreactions

A bstractWe employ the variational method for the Sturm-Liouville eigenvalue problem to analytically investigate the properties of the holographic superconductors. We find that the analytic method is still powerful when the backreaction is turned on. Reducing step size in the iterative procedure, we observe that the consistency of results between the analytic and numerical computations can be further improved. The obtained analytic result can be used to back up the numerical computations in the holographic superconductor in the fully backreacted spacetime.

Holographic entanglement entropy in general holographic superconductor models

A bstractWe study the entanglement entropy of general holographic dual models both in AdS soliton and AdS black hole backgrounds with full backreaction. We find that the entanglement entropy is a good probe to explore the properties of the holographic superconductors and provides richer physics in the phase transition. We obtain the effects of the scalar mass, model parameter and backreaction on the entropy, and argue that the jump of the entanglement entropy may be a quite general feature for the first order phase transition. In strong contrast to the insulator/superconductor system, we note that the backreaction coupled with the scalar mass can not be used to trigger the first order phase transition if the model parameter is below its bottom bound in the metal/superconductor system.

Holographic superconductor/insulator transition with logarithmic electromagnetic field in Gauss–Bonnet gravity

Abstract The behaviors of the holographic superconductors/insulator transition are studied by introducing a charged scalar field coupled with a logarithmic electromagnetic field in both the Einstein–Gauss–Bonnet AdS black hole and soliton. For the Einstein–Gauss–Bonnet AdS black hole, we find that: i) the larger coupling parameter of logarithmic electrodynamic field b makes it easier for the scalar hair to be condensed; ii) the ratio of the gap frequency in conductivity ω g to the critical temperature T c depends on both b and the Gauss–Bonnet constant α; and iii) the critical exponents are independent of the b and α. For the Einstein–Gauss–Bonnet AdS soliton, we show that the system is the insulator phase when the chemical potential μ is small, but there is a phase transition and the AdS soliton reaches the superconductor (or superfluid) phase when μ is larger than critical chemical potential. A special property should be noted is that the critical chemical potential is not changed by the coupling parameter b but depends on α.

Holographic superconductors in quintessence AdS black hole spacetime

We present a solution of Einstein equations describing a

Notes on analytical study of holographic superconductors with Lifshitz scaling in external magnetic field

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Holographic superconductor models in the non-minimal derivative coupling theory

-dimensional planar quintessence AdS black hole which depends on the state parameter

Geometric optics for a coupling model of electromagnetic and gravitational fields

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