Vertex correction and Ward identity in the U(1) gauge theory with Fermi surface

We show that introduction of vertex corrections in the fully self-consistent ladder approximation does not modify dynamics of spinons and gauge fluctuations in the U(1) gauge theory with Fermi surface

Categorification of Highest Weight Modules via Khovanov-Lauda-Rouquier Algebras

In this paper, we prove Khovanov-Lauda's cyclotomic categorification conjecture for all symmetrizable Kac-Moody algebras. Let $U_q(g)$ be the quantum group associated with a symmetrizable Cartan datum and let $V(\Lambda)$ be the irreducible highest weight $U_q(g)$-module with a dominant integral highest weight $\Lambda$. We prove that the cyclotomic Khovanov-Lauda-Rouquier algebra $R^{\Lambda}$ gives a categorification of $V(\Lambda)$.Comment: Typoes correcte

Superconductivity from a non-Fermi liquid metal : Kondo fluctuation mechanism in the slave-fermion theory

We find new mechanism of superconductivity beyond the spin-fluctuation theory, the standard model for unconventional superconductivity in the weak coupling approach, where Kondo fluctuations result in multi-gap superconductivity around an antiferromagnetic quantum critical point of the slave-fermion theory. Fingerprints of the hybridization mechanism are two kinds of resonance modes in not only spin but also charge fluctuations, originating from $d-wave$ pairing of conduction electrons and spinless holons, respectively, thus differentiated from the spin-fluctuation mechanism. We show that the ratio between each superconducting gap for conduction electrons $\Delta_{c}$ and holons $\Delta_{f}$ and the transition temperature $T_{c}$ is $2\Delta_{c} / T_{c} \sim 9$ and $2\Delta_{f} / T_{c} \sim \mathcal{O}(10^{-1})$, remarkably consistent with $CeCoIn_{5}$

Exactly Soluble Quantum Wormhole in Two Dimensions

We are presenting a quantum traversable wormhole in an exactly soluble two-dimensional model. This is different from previous works since the exotic negative energy that supports the wormhole is generated from the quantization of classical energy-momentum tensors. This explicit illustration shows the quantum-mechanical energy can be used as a candidate for the exotic source. As for the traversability, after a particle travels through the wormhole, the static initial wormhole geometry gets a back reaction which spoils the wormhole structure. However, it may still maintain the initial structure along with the appropriate boundary condition.Comment: v1. 13 pages, 1 figure, REVTeX3; v2. 1 Ref. added, REVTeX4, to appear in Phys. Rev.

Coulomb Driven New Bound States at the Integer Quantum Hall States in GaAs/Al(0.3)Ga(0.7)As Single Heterojunctions

Coulomb driven, magneto-optically induced electron and hole bound states from a series of heavily doped GaAs/Al(0.3)Ga(0.7)As single heterojunctions (SHJ) are revealed in high magnetic fields. At low magnetic fields (nu > 2), the photoluminescence spectra display Shubnikov de-Haas type oscillations associated with the empty second subband transition. In the regime of the Landau filling factor nu < 1 and 1 < nu <2, we found strong bound states due to Mott type localizations. Since a SHJ has an open valence band structure, these bound states are a unique property of the dynamic movement of the valence holes in strong magnetic fields

Antiferromagnetic metal to heavy-fermion metal quantum phase transition in the Kondo lattice model: A strong coupling approach

We study the quantum phase transition from an antiferromagnetic metal to a heavy fermion metal in the Kondo lattice model. Based on the strong coupling approach we {\it first} diagonalize the Kondo coupling term. Since this strong coupling approach makes the resulting Kondo term {\it relevant}, the Kondo hybridization persists even in the antiferromagnetic metal, indicating that fluctuations of Kondo singlets are not critical in the phase transition. We find that the quantum transition in our strong coupling approach results from {\it softening of antiferromagnetic spin fluctuations of localized spins}, driven by the Kondo interaction. Thus, the volume change of Fermi surface becomes continuous across the transition. .....

A criterion for the nature of the superconducting transition in strongly interacting field theories : Holographic approach

It is beyond the present techniques based on perturbation theory to reveal the nature of phase transitions in strongly interacting field theories. Recently, the holographic approach has provided us with an effective dual description, mapping strongly coupled conformal field theories to classical gravity theories. Resorting to the holographic superconductor model, we propose a general criterion for the nature of the superconducting phase transition based on effective interactions between vortices. We find "tricritical" points in terms of the chemical potential for U(1) charges and an effective Ginzburg-Landau parameter, where vortices do not interact to separate the second order (repulsive) from the first order (attractive) transitions. We interpret the first order transition as the Coleman-Weinberg mechanism, arguing that it is relevant to superconducting instabilities around quantum criticality.Comment: 7 pages, 7 figure