Publications by Fabian Essler

Application of massive integrable QFTs to problems in condensed matter physics

in From Fields to Strings: Circumnavigating Theoretical Physics: Ian Kogan Memorial Collection, 1 (2005) 684-

FHL Essler, RM Konik

© 2005 by World Scientific Publishing Co. Pte. Ltd. All rights reserved. We review applications of the sine-Gordon model, the 0(3) non-linear sigma model, the U(l) Thirring model, and the O(N) Gross-Neveu model to quasi one-dimensional quantum magnets, Mott insulators, and carbon nanotubes. We focus upon the determination of dynamical response functions for these problems. These quantities are computed by means of form factor expansions of quantum correlation functions in integrable quantum field theories. This approach is reviewed here in some detail.

Itinerancy effects on spin correlations in one-dimensional Mott insulators

PHYSICAL REVIEW B 71 (2005) ARTN 020405

MJ Bhaseen, FHL Essler, A Grage

The one-dimensional Hubbard model

Cambridge Univ Pr, 2005

FHL Essler, H Frahm, F Goehmann, A Kluemper, VE Korepin

Advanced level reference text on important topic in condensed matter physics, statistical and theoretical physics.

Resonant inelastic X-ray scattering of the holon-antiholon continuum in SrCuO2.

Phys Rev Lett 92 (2004) 137402-

Y-J Kim, JP Hill, H Benthien, FHL Essler, E Jeckelmann, HS Choi, TW Noh, N Motoyama, KM Kojima, S Uchida, D Casa, T Gog

We report a resonant inelastic x-ray scattering study of charge excitations in the quasi-one-dimensional Mott insulator SrCuO2. We observe a continuum of low-energy excitations, the onset of which exhibits a small dispersion of approximately 0.4 eV. Within this continuum, a highly dispersive feature with a large sinusoidal dispersion (approximately 1.1 eV) is observed. We have also measured the optical conductivity, and studied the dynamic response of the extended Hubbard model with realistic parameters, using a dynamical density-matrix renormalization group method. In contrast to earlier work, we do not find a long-lived exciton, but rather these results suggest that the excitation spectrum comprises a holon-antiholon continuum together with a broad resonance.

Haldane-gap chains in a magnetic field


FHL Essler, I Affleck

Dynamical response of quasi 1D Mott insulators


FHL Essler, AM Tsvelik

Dynamical structure factor of the anisotropic Heisenberg chain in a transverse field

PHYSICAL REVIEW B 68 (2003) ARTN 134431

JS Caux, FHL Essler, U Low

Finite temperature spectral function of Mott insulators and charge density wave states.

Phys Rev Lett 90 (2003) 126401-

FHL Essler, AM Tsvelik

We calculate the low-temperature spectral function of one-dimensional incommensurate charge density wave states and half filled Mott insulators. At T=0 there are two dispersing features associated with the spin and charge degrees of freedom, respectively. We show that already at very low temperatures (compared to the gap) one of these features gets severely damped. We comment on implications of this result for photoemission experiments.

Dynamical structure factor in copper benzoate and other spin-1/2 antiferromagnetic chains

PHYSICAL REVIEW B 68 (2003) ARTN 064410

FHL Essler, A Furusaki, T Hikihara

Polarization dependence of spin excitations in BaCu2Si2O7

PHYSICAL REVIEW B 67 (2003) ARTN 134406

A Zheludev, S Raymond, LP Regnault, FHL Essler, K Kakurai, T Masuda, K Uchinokura

Finite Temperature Spectral Function of Mott Insulators and Charge Density Wave States

Physical Review Letters 90 (2003) 126401 4pp-

FH Essler, A. Tsvelik

Weakly coupled one-dimensional Mott insulators

Physical Review B 65 (2002) 115117 13pp-

FH Essler, Tsvelik, A

Dynamical density correlation function of one-dimensional Mott insulators in a magnetic field

PHYSICAL REVIEW B 66 (2002) ARTN 165112

D Controzzi, FHL Essler

Quantum criticalities in a two-leg antiferromagnetic S=1/2 ladder induced by a staggered magnetic field

PHYSICAL REVIEW B 66 (2002) ARTN 024412

YJ Wang, FHL Essler, M Fabrizio, AA Nersesyan

Spectral function of a quarter-filled one-dimensional charge density wave insulator.

Phys Rev Lett 88 (2002) 096403-

FHL Essler, AM Tsvelik

We consider a one-dimensional charge density wave insulator formed by umklapp processes in a quarter-filled band. The spectrum of the model consists of gapless, uncharged excitations carrying spin +/- 1/2 (spinons) and gapped, spinless excitations carrying charge -/+ signe/2 (solitons and antisolitons). We calculate the low-energy behavior of the single-electron Green's function at zero temperature. The spectral function exhibits a featureless scattering continuum of two solitons and many spinons. The theory predicts that the gap observed by angle resolved photoemission is twice the activation gap in the dc conductivity. We comment on possible applications to PrBa(2)Cu(3)O(7) and to the Bechgaard salts.

Spectral Function of a Quarter-Filled One-Dimensional Charge Density Wave Insulator

Physical Review Letters 88 (2002) 096403 4pp-

FH Essler, A. Tsvelik

Optical conductivity of one-dimensional Mott insulators.

Phys Rev Lett 86 (2001) 680-683

D Controzzi, FH Essler, AM Tsvelik

We calculate the optical conductivity of one-dimensional Mott insulators at low energies using a field theory description. The square root singularity at the optical gap, characteristic of band insulators, is generally absent and appears only at the Luther-Emery point. We also show that only few particle processes contribute significantly to the optical conductivity over a wide range of frequencies and that the bare perturbative regime is recovered only at very large energies. We discuss possible applications of our results to quasi-one-dimensional organic conductors.

Dynamical properties of one dimensional Mott insulators


D Controzzi, FHL Essler, AM Tsvelik

Excitons in one-dimensional Mott insulators

PHYSICAL REVIEW B 64 (2001) ARTN 125119

FHL Essler, F Gebhard, E Jeckelmann

Finite-temperature dynamical magnetic susceptibility of quasi-one-dimensional frustrated spin-1/2 Heisenberg antiferromagnets

PHYSICAL REVIEW B 64 (2001) ARTN 094425

M Bocquet, FHL Essler, AM Tsvelik, AO Gogolin