Ground–state and dynamical properties of the 2D Holstein t–J model are examined by means of direct Lanczos diagonalization, using a truncation method of the phononic Hilbert space. The single– hole spectral function shows the formation of a narrow hole–polaron band as the electron–phonon coupling increases, where the polaronic band collapse is favoured by strong Coulomb correlations. In the two...

Based on the spin-blockade model for organic magnetoresistance, we present an analytic expression for the polaron-bipolaron transition rate, taking into account the effective nuclear fields on the two sites. We reveal the physics behind the qualitatively different magnetoconductance line shapes observed in experiment, as well as the ultrasmall magnetic field effect (USFE). Since our findings ag...

The intrachain recombination dynamics between oppositely charged polarons is theoretically investigated through the use of a version of the Su-Schrieffer-Heeger (SSH) model modified to include an external electric field, an extended Hubbard model, Coulomb interactions, and temperature effects in the framework of a nonadiabatic evolution method. Our results indicate notable characteristics conce...

Developed originally for the Holstein polaron, the Davydov D1 ansatz is an efficient, yet extremely accurate trial state for time-dependent variation of the spin-boson model [N. Wu, L. Duan, X. Li, and Y. Zhao, J. Chem. Phys. 138, 084111 (2013)]. In this work, the Dirac-Frenkel time-dependent variational procedure utilizing the Davydov D1 ansatz is implemented to study entanglement dynamics of ...

Scattering process between a negative polaron and an exciton in a polymer chain is investigated by using the Su-Schrieffer-Heeger model modified to include electron-electron interactions, the Brazovskii-Kirova symmetry breaking term, and an external electric field. It is found that the scattering process is spin dependent. If the polaron and the exciton have parallel spins, the polaron can easi...

The main objective of this thesis is to provide a deeper understanding of the charge transport phenomena occuring in molecular crystals. The focus is on the stability and the dynamics of the polaron as the charge carrier. To achieve this goal, a series of numerical calculations are performed using the semi-emprical "Holstien-Peierls" model. The model considers both intra(Holstein) and inter(Pei...

A system of a single relativistic electron interacting with the quantized electromagnetic field is considered. We mainly study this system with a fixed total momentum p — This system is called the Dirac polaron. We analyze the lowest energyE(p) of the Dirac polaron, and derive some properties: concavity, symmetricity, and the inverse energy inequality E(p) ≤ E(0), p ∈ R. Furthermore, we conside...

We study the formation of magnon-polaron excitations and consequences different time scales between magnon lattice dynamics. The spin-spin interactions along 1D are ruled by a Heisenberg Hamiltonian in anisotropic form XXZ, which each spin exhibits vibrational degree freedom around its equilibrium position. By considering magnetoelastic coupling as linear function relative displacement nearest-...

The interplay between measurement and quantum correlations in many-body systems can lead to novel types of collective phenomena which are not accessible isolated systems. In this work, we merge the Zeno-paradigm theory with concept polarons condensed-matter physics. resulting quantum-Zeno Fermi-polaron is a quasi-particle emerges for lossy impurities interacting quantum-degenerate bath fermions...

A low-energy theory of suspended carbon nanotube quantum dots in weak tunnelling coupling with metallic leads is presented. The focus is on the dependence of the spectrum and the Franck–Condon factors on the geometry of the junction including several vibronic modes. The relative size and the relative position of the dot and its associated vibrons strongly influence the electromechanical propert...