Relevant coherent states method for the quantum adiabatic dynamics of lattice-coupled charge carriersO. S. Barisic
Institute of Physics - Bijenicka c. 46, HR-10000 Zagreb, Croatia
received 12 September 2006; accepted in final form 9 January 2007; published March 2007
published online 20 February 2007
A new numerical method is proposed for determining the low-frequency dynamics of the charge carrier coupled to the deformable quantum lattice. As an example, the polaron band structure is calculated for the one-dimensional Holstein model. The adiabatic limit on the lattice, which cannot be reached by other approaches, is investigated. In particular, an accurate description is obtained of the crossover between quantum small adiabatic polarons, pinned by the lattice, and large adiabatic polarons, moving along the continuum as classical particles. It is shown how the adiabatic contributions to the polaron dispersion, involving spatial correlations over multiple lattice sites, can be treated easily in terms of coherent states.
71.38.-k - Polarons and electron-phonon interactions.
63.20.Kr - Phonon-electron and phonon-phonon interactions.
© Europhysics Letters Association 2007