We show that we can realize the surface state together with the bulk state of various types of topological matters in holographic context, by considering various types of Lorentz symmetry breaking. The fermion spectral functions in the presence of order show features like the gap, pseudo-gap, flat disk bands and the Fermi-arc connecting the two Dirac cones, which are familiar in...
We consider the magneto-transports of quantum matters doped with magnetic impurities near the quantum critical points (QCP). For this, we first find new black hole solution with hyper-scaling violation which is dual to such system. By considering the fluctuation near this exact solution, we calculated all transport coefficients using the holographic method. We applied our result...
AbstractIt is often said that interactions destroy the particle nature of excitations. We report that, in holographic theory adding interaction term can create a new quasi particle spectrum, on the contrary. We show this by calculating the optical conductivity in a model with exact background solution and finding a new quasi-particle spectrum. Such new poles are consequence of...
Abstract We study the spontaneous magnetization and the magnetic hysteresis using the gauge/gravity duality. We first propose a novel and general formula to compute the magnetization in a large class of holographic models. By using this formula, we compute the spontaneous magnetization in a model like a holographic superconductor. Furthermore, we turn on the external magnetic...
Abstract We show that the Mott transition can be realized in a holographic model of a fermion with bulk mass, m, and a dipole interaction of coupling strength p. The phase diagram contains gapless, pseudo-gap and gapped phases and the first one can be further divided into four sub-classes. We compare the spectral densities of our holographic model with the Dynamical Mean Field...
Abstract Recent discovery of transport anomaly in graphene demonstrated that a system known to be weakly interacting may become strongly correlated if system parameter (s) can be tuned such that fermi surface is sufficiently small. We study the strong correlation effects in the transport coefficients of Dirac materials doped with magnetic impurity under the magnetic field using...
We study the thermoelectric conductivities of a strongly correlated system in the presence of a magnetic field by the gauge/gravity duality. We consider a class of Einstein-Maxwell-Dilaton theories with axion fields imposing momentum relaxation. General analytic formulas for the direct current (DC) conductivities and the Nernst signal are derived in terms of the black hole...
We study AC electric (σ), thermoelectric (α), and thermal \( \left(\overline{\kappa}\right) \) conductivities in a holographic model, which is based on 3+1 dimensional Einstein-Maxwell-scalar action. There is momentum relaxation due to massless scalar fields linear to spatial coordinate. The model has three field theory parameters: temperature (T), chemical potential (μ), and...
We study the baryon density dependence of the vector meson spectrum using the D4/D6 system together with the compact D4 baryon vertex. We find that the vector meson mass decreases almost linearly in density at low density for small quark mass, but saturates to a finite non-zero value for large density. We also compute the density dependence of the η′ mass and the η′ velocity. We...
We investigate the D3–D7 model at finite U(1)B-charge chemical potential. We point out that the D3–D7 model with only the black-hole embeddings does not have the low-temperature and low-chemical-potential region in the grand-canonical ensemble, hence it is incomplete. The incomplete-ness is also seen as the thermodynamic instability in the canonical ensemble. We propose to solve...