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We explored the interplay between magnetic field and rotation in the de Hass - van Alphen oscillation. The effect is found to be reduced because of the re-weighting of different states within the same Landau level by rotation energy. The implications of our results on high energy physics and condensed matter physics are speculated., Comment: 21 pages, 9 figures in Revtex

The chiral magnetic effect with a fluctuating chiral imbalance is more realistic in the evolution of quark-gluon plasma, which reflects the random gluonic topological transition. Incorporating this dynamics, we calculate the chiral magnetic current in response to space-time dependent axial gauge potential and magnetic field in AdS/CFT correspondence. In contrast to conventional treatment of constant axial chemical potential, the response function here is the AVV three-point function of the $\mathcal{N}=4$ super Yang-Mills at strong coupling. Through an iterative solution of the nonlinear equations of motion in Schwarzschild-AdS$_5$ background, we are able to express the AVV function in terms of two Heun functions and prove its UV/IR finiteness, as expected for $\mathcal{N}=4$ super Yang-Mills theory. We found that the dependence of the chiral magnetic current on a non-constant chiral imbalance is non-local, different from hydrodynamic approximation, and demonstrates the subtlety of the infrared limit discovered in field theoretic approach. We expect our results enrich the understanding of the phenomenology of the chiral magnetic effect in the context of relativistic heavy ion collisions., Comment: 36 pages, 2 figure

We investigate the axial vortical effect in a uniformly rotating sphere subject to finite size. We use MIT boundary condition to limit the boundary of the sphere. For massless fermions inside the sphere, we obtain the exact axial vector current far from the boundary that matches the expression obtained in cylindrical coordinates in the literature. On the spherical boundary, we find both the longitudinal and transverse(with respect to the rotation axis) components with magnitude depending on the colatitude angle. For massive fermions, we derive an expansion of the axial conductivity far from the boundary to all orders of mass whose leading order term agrees with the mass correction reported in the literature. We also obtain the leading order mass correction on the boundary which is linear, and stronger than the quadratic dependence far from the boundary. The qualitative implications on the phenomenology of heavy ion collisions are speculated., Comment: 35 pages, 4 figures

The response of chiral fermions to time and space dependent axial imbalance & constant magnetic field is analyzed. The axialvector-vector-vector (AVV) three-point function is studied using a real-time approach at finite temperature in the weak external field approximation. The chiral magnetic conductivity is given analytically for noninteracting fermions. It is pointed out that local charge conservation plays an important role when the axial imbalance is inhomogeneous. Proper regularization is needed which makes the constant axial imbalance limit delicate: for static but spatially oscillating chiral charge the current of the chiral magnetic effect (CME) vanishes. In the homogeneous (but possible time-dependent) limit of the axial imbalance the CME current is determined solely by the chiral anomaly. As a phenomenological consequence, the observability of the charge asymmetry caused by the CME turns out to be a matter of interplay between various scales of the system. Possible plasma instabilities resulting from the gradient corrections to the CME current are also pointed out., 21 pages, 5 figures. v2: substantial changes of text, fig. 3 updated, practically matches journal version

We study the noncommutativity of different orders of zero energy-momentum limit pertaining to the axial chemical potential in the chiral magnetic effect. While this noncommutativity issue originates from the pinching singularity at one-loop order, it cannot be removed by introducing a damping term to the fermion propagators. The physical reason is that modifying the propagator alone would violate the axial-vector Ward identity and as a result a modification of the longitudinal component of the axial-vector vertex is required, which contributes to CME. The pinching singularity with free fermion propagators was then taken over by the singularity stemming from the dressed axial-vector vertex. We show this mechanism by a concrete example. Moreover, we proved in general the vanishing CME in the limit order that the static limit was taken prior to the homogeneous limit in the light of Coleman-Hill theorem for a static external magnetic field. For the opposite limit that the homogeneous limit is taken first, we show that the nonvanishing CME was a consequence of the nonrenormalizability of chiral anomaly for an arbitrary external magnetic field., Comment: 16 pages, 4 figures

Given the intrinsic nonequilibrium nature of high-energy collisions the investigation of the dynamical properties of transport phenomena is important. The study of the real-time behavior of various conductivities and susceptibilities help refine the simulation tools we use to compare the theories and the experimental findings. In this contribution we take steps to give the chiral magnetic conductivity in case of magnetic field and chiral imbalance are both space-time dependent. Using linear response approximation we present the general 1-loop resummed expression for the electric current. We also suggest simple limiting cases in hope for possible implementation into a hydrodynamical framework., Comment: 5 pages, 2 figures; contribution to the proceedings of the 8th International Conference on Quarks and Nuclear Physics (QNP2018), Tsukuba, November 13-17, 2018

The static electric polarization of a holographic field theory dual to the Einstein-Maxwell theory in the background of $AdS_4$ with a Reissner-Nordst\"{o}m (AdS-RN) black hole is investigated. We prove that the holographic polarization is a meromorphic functions in complex momentum plane and locate analytically the asymptotic distribution of the poles along two straight lines parallel to the imaginary axis for a large momentum magnitude. The results are compared with the numerical result on Friedel-like poles of the same holographic model reported in the literature and with the momentum singularities of the one-loop polarization in weak-coupling spinor QED$_3$ and scalar QED$_3$ with the similarities and differences discussed., Comment: 31 pages, 2 figures

We study in this paper the radiative corrections to chiral magnetic current at both zero and nonzero temperature. Our motivation is a radiative correction to the matrix element of the anomalous Ward identity in massless QED stemming from a three-loop diagram where the two photons coming from the one-loop anomalous triangle are re-scattered. Through the interplay between the Ward identity and the infrared subtlety of the fermion loop integral, we are able to reproduce the corrections known in literature in a simpler approach and obtain its contribution to the chiral magnetic current at zero temperature. At a nonzero temperature, the infrared subtlety disappeared in a static magnetic field and the three-loop diagram does not contribute to the chiral magnetic current any more. The generalization to all orders of the massless QED and the QCD corrections are discussed., 15 pages, 3 figures

The (2+1)-dimensional static magnetic susceptibility in strong-coupling is studied via a Reissner-Nordstr\"{o}m-AdS geometry. The analyticity of the susceptibility on the complex momentum $\mathfrak{q}$-plane in relation to the Friedel-like oscillation in coordinate space is explored. In contrast to the branch-cuts crossing the real momentum-axis for a Fermi liquid, we prove that the holographic magnetic susceptibility remains an analytic function of the complex momentum around the real axis in the limit of zero temperature, At zero temperature, we located analytically two pairs of branch-cuts that are parallel to the imaginary momentum-axis for large $|\text{Im}\ \mathfrak{q}|$ but become warped with the end-points keeping away from the real and imaginary momentum-axes. We conclude that these branch-cuts give rise to the exponential decay behaviour of Friedel-like oscillation of magnetic susceptibility in coordinate space. We also derived the analytical forms of the susceptibility in large and small-momentum, respectively., Comment: 2 figure, big changes from the first version

We assess the applicability of the Wigner function formulation in its present form to the chiral magnetic effect and note some issues regarding the conservation and the consistency of the electric current in the presence of an inhomogeneous and time-dependent axial chemical potential. The problems are rooted in the ultraviolet divergence of the underlying field theory associated with the axial anomaly and can be fixed with the Pauli-Villars regularization of the Wigner function. The chiral magnetic current with a nonconstant axial chemical potential is calculated with the regularized Wigner function and the phenomenological implications are discussed.

We study analytically the one-loop contribution to the Chiral Magnetic Effect(CME) using lattice regularization with a Wilson fermion field. In the continuum limit, we find that the chiral magnetic current vanishes at nonzero temperature but emerges at zero temperature consistent with that found by Pauli-Villas regularization. For finite lattice size, however, the chiral magnetic current is nonvanishing at nonzero temperature. But the numerical vaule of the coefficient of CME current is very small compared with that extracted from the full QCD simulation for the same lattice parameters. The possibility of higher order corrections from QCD dynamics is also assessed., 7 pages

We explore the momentum analyticity of the static transverse polarization tensor of a 2+1 dimensional holographic superconductor in its normal phase with a nonzero chemical potential, aiming at finding the holographic counterpart of the singularities underlying the Friedel-like oscillations of an ordinary field theory. We prove that the polarization tensor is a meromorphic function with an infinite number of poles located on the complex momentum plane off real axis. With the aid of the WKB approximation these poles are found to lies asymptotically along two straight lines parallel to the imaginary axis for a large momentum magnitude. The similarity between the holographic Green's function and that of an weakly coupled ordinary field theory (e.g., 2+1 dimensional QED) regarding the location of the momentum singularities offers further support to the validity of the gauge/gravity duality., Comment: 17 pages, 2 figures

The Bose-Einstein condensation of bound pairs made of equally and oppositely charged fermions in a magnetic field is investigated using a relativistic model. The Gaussian fluctuations have been taken into account in order to study the spectrum of bound pairs in the strong coupling region. We found, in weak coupling reagion, the condensation temperature increases with an increasing magnetic field displaying the magnetic catalysis effect. In strong coupling region, the inverse magnetic catalysis appears when the magnetic field is low and is replaced by the usual magnetic catalysis effect when magnetic field is sufficiently high, in contrast to the nonrelativistic case where the inverse magnetic catalysis prevails in strong coupling region regardless of the strength of the magnetic field. The resulting response to the magnetic field is the consequence of the competition between the dimensional reduction by Landau orbitals in pairing dynamics and the anisotropy of the kinetic spectrum of the bound pairs. We thus conclude that dimensional reduction dominates in weak domain and strong coupling one except the small magnetic field region, where the enhanced fluctuations dominates., Typos fixed, a few references added, 16 pages, 8 figures,1 table , in Latex

Because of the equal strength of the pairing potential mediated by one-gluon exchange for all partial waves to the leading order QCD running coupling constant and the nonlinearity of the gap equation, the non-spherical pairing in single flavor color superconductivity(CSC) can not be restricted in a single non-s-wave channel and the mixing among different angular momenta will occur. In this paper, we examine the angular momentum mixing in single flavor CSC with transverse pairing, in which the pairing quarks have opposite helicity. We find that the free energy of all non-spherical pairing states are lowered by angular momentum mixing compared with that contain p-wave only. But the amount of the free energy drop is numerically small. Consequently the most stable pairing state that respect the time reversal invariance remains the spherical CSL., Comment: 16 pages, 2 figures, 1 table in Revtex

We study the Anderson Localization effect on the shear viscosity in a system with random medium by Kubo formula. We show that this effect can reduce the shear viscosity nonperturbatively. Then we discuss its possible implementation in heavy-ion collisions, where the created heavy bound states or other collective modes may play the role of the random scatterer underlying Anderson Localization effect.

The Bose-Einstein condensation of bound pairs made of oppositely charged fermions in a magnetic field is investigated. We find that the condensation temperature shows the magnetic catalysis effect in weak coupling and the inverse magnetic catalysis effect in strong coupling. The different responses to the magnetic field can be attributed to the competition between the dimensional reduction by Landau orbitals in pairing dynamics and the anisotropy of the kinetic spectrum of fluctuations (bound pairs in the normal phase)

We calculate the magnetic polarization tensor of the photon and of the gluons in a two flavor color superconductor with a LOFF pairing that consists of a single plane wave. We show that at zero temperature and within the range of the values of the displacement of the Fermi sea that favors the LOFF state, all the eigenvalues of the magnetic polarization tensor are positive. Therefore the chromomagnetic instabilities pertaining to a gapless color superconductor disappear., Comment: 20 pages and 7 figures, Latex, typos were corrected, references added

In a braneworld context, the radion is a massless mode coupling to the trace of the matter stress tensor. Since the radion also governs the separation between branes, it is expected to decouple from the physical spectrum in single brane scenarios, such as the one-brane Randall-Sundrum model. However, contrary to expectations, we demonstrate that the Karch-Randall radion always remains as a physical excitation, even in the single brane case. Here, the radion measures the distance not between branes, but rather between the brane and the anti-de Sitter boundary on the other side of the bulk., 19 pages, Plain Tex

We give a proof of a local relation between the inverse Faddeev–Popov operator and the non-Abelian Coulomb interaction between color charges.

We solve the Einstein equations in the Dvali-Gabadadze-Porrati model with a static, spherically symmetric matter distribution on the physical brane and obtain an exact expression for the gravitational field outside the source to the first order in the gravitational coupling. Although when confined on the physical brane this expression reproduces the correct 4D Newtonian potential for distances r_s << r << {\lambda}, where {\lambda} is a characteristic length scale of the model, it does not coincide with the standard linearized form of the 4D Schwarzschild metric. The solution reproduces the 5D Schwarzschild metric in the linearized approximation for r >> {\lambda}., Comment: 9 pages, plain Tex, no figures

The general Ginzburg-Landau formulation of a holographic superconductor is developed near the transition temperature in the probe limit for two kinds of conformal dimension. Below the transition temperature, $T, Comment: Typos fixed, 29 pages in Revtex

The normal phase electron spectral function is calculated with the Boson–Fermion model to one loop order for both D =2 and D =3 cases. The presence of the pseudo-gap in D =2 and its absence in D =3 suggests the importance of the quasi-2D nature of the cuprate crystal to the observed pseudo-gap above T c . The same reasoning underlying this dimension dependence leads to a diagrammatic resummation of the electron propagator in D =2, which established the pseudo-gap behavior beyond mean field approximation. Possible experimental tests of the dimension dependence are considered.

The high-$T_c$ cuprates are possible candidates for d-wave superconductivity, with the Cooper pair wave function belonging to a non-trivial irreducible representation of the lattice point group. We argue that this d-wave symmetry is related to a special form of the fermionic kinetic energy and does not require any novel pairing mechanism. In this context, we present a detailed study of the bound states and resonances formed by two lattice fermions interacting via a non-retarded potential that is attractive for nearest neighbors but repulsive for other relative positions. In the case of strong binding, a pair formed by fermions on adjacent lattice sites can have a small effective mass, thereby implying a high condensation temperature. For a weakly bound state, a pair with non-trivial symmetry tends to be smaller in size than an s-wave pair. These and other findings are discussed in connection with the properties of high-$T_c$ cuprate superconductors., 21 pages, RevTeX, 4 Postscript figures, arithmetic errors corrected. An abbreviated version (no appendix) appeared in PRB on March 1, 1997

We derive the quadratic action of the fluctuations around the classical world sheet underlying the jet quenching from AdS/CFT. After obtaining the correspondence partition function, the expansion of the jet quenching parameter of $\mathcal N=4$ super symmetric Yang-Mills theory is carried out to the sub-leading term in the large 't Hooft coupling $\lambda$ at a nonzero temperature. The strong coupling corresponds to the semi-classical expansion of the string-sigma model, the gravity dual of the Wilson loop operator, with the sub-leading term expressed in terms of functional determinants of fluctuations. The contribution of these determinants are evaluated numerically. We find the jet quenching parameter is reduced due to world sheet fluctuations by a factor $(1-1.97\lambda^{-1/2}) $, Comment: 34 pages, 2 figures, updated version accepted to be published in JHEP, with typos corrected and a few references added

The relativistic correction of the AdS/CFT implied heavy quark potential is examined within the framework of the potential model. For the typical range of the coupling strength appropriate to heavy-ion collisions, we find the correction is significant in size and lowers the dissociation temperature of quarkonia., 11 pages, 2 tables in latex

Applying the AdS/CFT correspondence, the expansion of the heavy-quark potential of the N = 4 supersymmetric Yang-Mills theory at large Nc is carried out to the sub-leading term in the large ’t Hooft coupling at a nonzero temperature. The strong coupling corresponds to the semiclassical expansion of the string-sigma model, the gravity dual of the Wilson loop operator, with the sub-leading term expressed in terms of functional determinants of fluctuations. The contribution of these determinants are evaluated numerically. We also discuss some physics consequences of the subleading heavy quark potential.

For any purely fermionic system on a lattice in arbitrary space dimension we prove that there is a different but well-defined system on the same lattice, consisting of both bona fide fermions and bosons with an interaction depending on a parameter \ensuremath{\lambda}, which characterizes a same-site repulsion between particles. The energy spectrum and the scattering matrix of the former are identical to those in the finite energy sector of the latter, in the limit \ensuremath{\lambda}\ensuremath{\rightarrow}\ensuremath{\infty} (i.e., hard-core repulsion). This general theorem is applied to a resonance-boson model in a lattice fermion system, whose solution may have relevance to high-${\mathit{T}}_{\mathit{c}}$ superconductivity.

We report the static magnetization measurements of a few graphene layers on hexagonal boron nitride substrates (gra/h-BN) prepared by chemical vapor deposition. No ferromagnetic signal is detected for the gra/h-BN structures at temperatures between 5 and 300 K. At high temperatures ($Tg100$ K), the gra/h-BN structures are diamagnetic with mass magnetic susceptibilities independent of temperature and close to, or slightly larger than, that of h-BN substrates. At low temperatures ($Tl20$ K), the gra/h-BN structures exhibit paramagnetic responses, which depend sensitively on the growth time of the graphene layers. The origin of this paramagnetism is attributed to the localized spins of the point defects in the graphene layers. The angular momentum number of these spins is $J=1/2$ and is derived by fitting the magnetization data after subtraction of the diamagnetic background of the h-BN substrates to the standard Brillouin functions. A saturated mass magnetization of about 0.13 to 0.25 emu/g at $T=5$ K is estimated for our gra/h-BN samples. At temperatures between 20 and 50 K, the measured magnetic susceptibilities of the gra/h-BN samples deviate significantly from that of a Curie-type paramagnetic material. A local maximum is found in the temperature dependence of the magnetic susceptibilities of our gra/h-BN samples. Several possible explanations, including the Ruderman-Kittle-Kasuya-Yosida interactions among local magnetic moments and the itinerant electrons in the graphene/h-BN interfaces in our gra/h-BN samples, are discussed and compared to the experimental results.

The nonzero strange quark mass effect in different types of single flavor color superconductivity and the phase diagram in a magnetic field are studied. We have obtained simple analytical forms of the quasi-particle energies for an arbitrary mass and explored the mass correction to the pressure and the transition temperature. It is found that the mass reduces the pressure and transition temperature of strange quarks, but it doesn't change the ranking $P_n, Comment: 16 pages in Revtex with 3 EPS-figures

In this paper, we shall address some field theoretic issues regarding the chiral magnetic effect. The general structure of the magnetic current consistent with the electromagnetic gauge invariance is obtained and the impact of the infrared divergence is examined. Some subtleties on the relation between the chiral magnetic effect and the axial anomaly are clarified through a careful examination of the infrared limit of the relevant thermal diagrams., Comment: 19 pages, 4 figures in Latex. Typos fixed, version accepted to be published in JHEP

We calculate the energy release associated with first-order phase transition between different types of single flavor color superconductivity in a magnetic field., Updated version accepted by PRD, with minor changes

Applying the AdS/CFT correspondence, the expansion of the heavy-quark potential of the ${\cal N}$ supersymmetric Yang-Mills theory at large $N_c$ is carried out to the sub-leading term in the large 't Hooft coupling at nonzero temperatures. The strong coupling corresponds to the semi-classical expansion of the string-sigma model, the gravity dual of the Wilson loop operator, with the sub-leading term expressed in terms of functional determinants of fluctuations. The contributions of these determinants are evaluated numerically., Comment: 17 pages in JHEP3, typos fixed, updated version to be published in JHEP

We investigate the single flavor color superconductivity in a magnetic field. Because of the absence of the electromagnetic Meissner effect, forming a nonspherical CSC phase, polar, A or planar, does not cost energy of excluding magnetic flux. We found that these nonspherical phases do occupy a significant portion of the phase diagram with respect to magnetic field and temperature and may be implemented under the typical quark density and the magnetic field inside a compact star., 4 pages minor changes, typos fixed, figures redrawn

The momentum plane analyticity of two point function of a relativistic thermal field theory at zero chemical potential is explored. A general principle regarding the location of the singularities is extracted. In the case of the N=4 supersymmetric Yang-Mills theory at large $N_c$, a qualitative change in the nature of the singularity (branch points versus simple poles) from the weak coupling regime to the strong coupling regime is observed with the aid of the AdS/CFT correspondence., Comment: 18 pages, 3 figures, typos fixed, 1 figure updated

We show that the near degeneracy of the low-lying vector (${\mathit{T}}_{1\mathit{u}}$) and axial-vector (${\mathit{T}}_{1\mathit{g}}$) levels in an isolated ${\mathrm{C}}_{60}^{\mathrm{\ensuremath{-}}}$ can provide a simple pairing mechanism in ${\mathrm{C}}_{60}^{2\mathrm{\ensuremath{-}}}$, ${\mathrm{C}}_{60}^{3\mathrm{\ensuremath{-}}}$, and the ${\mathrm{K}}_{\mathit{n}}$${\mathrm{C}}_{60}$ crystal. This gives rise to the possibility of a ``boson'' band in ${\mathrm{K}}_{\mathit{n}}$${\mathrm{C}}_{60}$, in addition to the usual fermion bands. The implications for superconductivity are discussed.

We examine the one-loop partition function describing the fluctuations of the superstring in a Schwarzschild-AdS{sub 5}xS{sup 5} background. On the bosonic side, we demonstrate the one-loop equivalence of the Nambu-Goto action and the Polyakov action for a general world sheet, while on the fermionic side, we consider the reduction of the ten-dimensional Green-Schwarz fermion action to a two-dimensional world sheet action. We derive the partition functions of the world sheets corresponding to both straight and parallel Wilson lines. We discuss the cancellation of the UV divergences of the functional determinants in the thermal AdS background.

We study the Anderson localization effect on the shear viscosity in a system with random medium by Kubo formula. We show that this effect can suppress nonperturbatively the shear viscosity and other transport coefficients. The possible relevancy of such a suppression to the near perfect fluid behavior of the quark-gluon plasma created in heavy-ion collisions is discussed.

We develop a formalism for defining and studying the form factors which describe the coupling of a spin-{ital J} particle through a conserved tensor current to a spin-{ital S} boson. For {ital S}=2, these form factors are the single-graviton gravitational form factors. We investigate the behavior of the various form factors under {ital C}, {ital P}, {ital T}, and {ital CPT} and classify them accordingly. We show that under {ital CPT} invariance all the multipoles of the mass distribution are the same for a particle and its antiparticle. We also show that in a quantum theory of gravity the coupling of a particle to the graviton is in general different from that of its antiparticle. Only when {ital P} and {ital T} are both valid symmetries of the underlying theory do a particle and its antiparticle couple identically to the graviton. The number of form factors for arbitrary {ital J} and {ital S} is given. We show that a massive Majorana particle (a {ital CPT} self-conjugate particle) coupling to an odd-spin boson possesses only anapole moments. Massless Majorana particles with spin{ne}1/2 have no single-photon electromagnetic form factors while the ones with spin{ne}1/2, 1, or 3/2 have no interactions with amore » spin-3 boson; this applies to the graviton ({ital J}=2, {ital S}=1,3) and to the massless gravitino ({ital J}=3/2, {ital S}=1). Our results also apply to extended objects (nuclei, . . .) in the low-energy limit.« less

We study the angular momentum mixing effects in the color superconductor with non-spherical pairing. We first clarify the concept of the angular momentum mixing with a toy model for non-relativistic and spinless fermions. Then we derive the gap equation for the polar phase of dense QCD by minimizing the CJT free energy. The solution of the gap equation consists of all angular momentum partial waves of odd parity. The corresponding free energy is found to be lower than that reported in the literature with p-wave only., 17 pages, 2 figues, in latex; References added, typos fixed

The fluctuations of the Higgs and pseudo Nambu-Goldstone fields in the 2SC phase with mismatched pairing are described in the nonlinear realization framework of the gauged Nambu--Jona-Lasinio model. In the gapless 2SC phase, not only Nambu-Goldstone currents can be spontaneously generated, but the Higgs field also exhibits instablity. The Nambu-Goldstone currents generation indicates the formation of the single plane wave LOFF state and breaks rotation symmetry, while the Higgs instability favors spatial inhomogeneity and breaks translation invariance. In this paper, we focus on the Higgs instability which has not drawn much attention yet. The Higgs instability cannot be removed without a long range force, thus it persists in the gapless superfluidity and induces phase separation. In the case of g2SC state, the Higgs instability can only be partially removed by the electric Coulomb energy. However, it is not excluded that the Higgs instability might be completely removed in the charge neutral gCFL phase by the color Coulomb energy., 21 pages, 5 figures

We use the Ginzburg-Landau theory near the transition temperature in order to examine the behavior of an inhomogeneous superconductor in the presence of a magnetic field. We find that a transition from type-I to type-II superconductivity occurs. Furthermore we calculate the critical value of the mismatch and estimate the contributions of the fluctuations of the condensate and the higher-order terms in the Ginzburg-Landau framework.

The quarkonium states in a quark-gluon plasma is examined with the heavy quark potential implied by the holographic principle. Both the vanila AdS-Schwarzschild metric and the one with an infrared cutoff are considered. The dissociation temperature is calculated by solving the Schr\"o dinger equation of the potential model. In the case of the AdS-Schwarzschild metric with a IR cutoff, the dissociation temperatures for $J/\psi$ and $\Upsilon$ with the U-ansatz of the potential are found to agree with the lattice results within a factor of two., Comment: 9 pages with 2 figues in Revtex

In this letter we explore the Higgs instability in the gapless superfluid/superconducting phase. This is in addition to the (chromo)magnetic instability that is related to the fluctuations of the Nambu-Goldstone bosonic fields. While the latter may induce a single-plane-wave LOFF state, the Higgs instability favors spatial inhomogeneity and cannot be removed without a long range force. In the case of the g2SC state the Higgs instability can only be partially removed by the electric Coulomb energy. But this does not exclude the possibility that it can be completely removed in other exotic states such as the gCFL state., 4 pages, 2 figure, one figure added

We clarify general properties of the energy gap regarding its functional dependence on the energy-momentum dictated by the invariance under a space inversion or a time reversal. Then we derive perturbatively the equation of the imaginary part of the gap function for dense QCD in weak coupling and generalize our results from 2SC case to CFL case. We confirm that the imaginary part is down by $g$ relative to the real part in weak coupling. The numerical results show that, up to the leading order, the imaginary part is no larger than one MeV at extremely large densities and can be as large as several MeV the densities are of physical interest., 15 pages, 2 figures, typos corrected, a figure replaced. The version to be appeared in Nucl.Phys. B

We study the effects of gauge-field fluctuations on the free energy of a homogeneous color superconductor in the color-flavor-locked (CFL) phase. Gluonic fluctuations induce a strong first-order phase transition, in contrast to electronic superconductors where this transition is weakly first order. The critical temperature for this transition is larger than the one corresponding to the diquark pairing instability. The physical reason is that the gluonic Meissner masses suppress long-wavelength fluctuations as compared to the normal conducting phase where gluons are massless, which stabilizes the superconducting phase. In weak coupling, we analytically compute the temperatures associated with the limits of metastability of the normal and superconducting phases, as well as the latent heat associated with the first-order phase transition. We then extrapolate our results to intermediate densities and numerically evaluate the temperature of the fluctuation-induced first-order phase transition, as well as the discontinuity of the diquark condensate at the critical point. We find that the London limit of magnetic interactions is absent in color superconductivity., Comment: 14 pages, 5 figures

Type-I color superconductors display a first-order phase transition due to thermal gauge-field fluctuations. We numerically evaluated the critical temperature of the first-order phase transition and the corresponding discontinuity of the diquark condensate at the critical point., 4 pages, 1 figure, to appear in the proceedings of 18th International Conference on Ultrarelativistic Nucleus-Nucleus Collisions: Quark Matter 2005 (QM 2005), Budapest, Hungary, 4-9 Aug 2005, grant information updated, no other changes

In this paper we construct analytically a LOFF color superconducting state that is both color and charge neutral using the weak coupling approximation. We demonstrate that this state is free from chromomagnetic instabilities. Its relevance to the realistic quark matter at moderately high baryon density is discussed., 9 pages, Latex, correction of algebraic mistake and typos