Emergence of states in the phonon spectral function of the Holstein polaron below and above the one-phonon continuum

Abstract

We investigate the low-energy properties of the Holstein polaron through calculation of the q-dependent phonon spectral function using an improved exact-diagonalization technique, defined over a variational Hilbert space. We perform a comprehensive study of the low-energy excitations of the polaron. Beside the energy range, where the additional phonon excitation is unbound, we observe separate coherent peaks which correspond to bound and antibound states of a polaron and additional phonon quanta. These novel states can be observed for intermediate and strong electron-phonon coupling strengths, as well as below and above the unbound one-phonon excitation spectrum. A detailed investigation of their properties is presented. We find good agreement between the phonon spectral function obtained from the first-order strong-coupling perturbation theory and numerical results.

10 pages, 8 figures

References in corpus (7)

• The Green's Function of the Holstein Polaron
• Interplay between electron-phonon and Coulomb interactions in cuprates
• Systematic improvement of the Momentum Average approximation for the Green's function of a Holstein polaron
• Ground state properties of the Holstein model near the adiabatic limit
• Phase diagram of the Holstein polaron in one dimension
• Phonon spectral function of the Holstein polaron
• Relevant coherent states method for the quantum adiabatic dynamics of lattice-coupled charge carriers

Cited by in corpus (12)

• Nonequilibrium dynamics of the Holstein polaron driven by external electric field
• Relaxation dynamics of the Holstein polaron
• Real-time decay of a highly excited charge carrier in the one-dimensional Holstein model
• Charge-density-wave melting in the one-dimensional Holstein model
• Finite-temperature density-matrix renormalization group method for electron-phonon systems: Thermodynamics and Holstein-polaron spectral functions
• Spectral and thermodynamic properties of the Holstein polaron: Hierarchical equations of motion approach
• Discontinuous polaron transition in a two-band model
• Finite-temperature optical conductivity with density-matrix renormalization group methods for the Holstein polaron and bipolaron with dispersive phonons
• Polaron transformations in the realistic model of the strongly correlated electron system
• Chebyshev pseudosite matrix product state approach for the spectral functions of electron-phonon coupling systems
• Adiabatic theory of the polaron spectral function
• Diagrammatic quantum Monte Carlo study of an acoustic lattice polaron