We present numerically exact solutions to the problem of a single electron interacting through an extended interaction with optical phonons in two and three dimensions. Comparisons are made with results for the standard Holstein model and with perturbative approaches from both the weak coupling and strong coupling sides. We find, in agreement with earlier work, that the polaron effective mass increases (decreases) in the weak (strong) coupling regime, respectively. However, in two dimensions, the decrease in effective mass still results in too large an effective mass to be relevant in realistic models of normal metals. In three dimensions the decrease can be more relevant but exists only over a very limited range of coupling strengths.
Physical Review B
- Pub Date:
- September 2014
- Large or Frohlich polarons;
- Self-trapped or small polarons;
- Condensed Matter - Strongly Correlated Electrons
- 9 pages, 8 figures