Fractal lattice as an efficient thermoelectric device

Abstract

Figure of merit is an essential quantity to describe the efficiency of a thermoelectric device and asymmetry in transmission probability is the main requirement to increase the efficiency. Keeping this fact in the mind, here we choose a Sierpinski Gasket (SPG) triangle, a nice example of fractal lattice, as the functional element since it has peculiar energy spectrum compared to the traditional elements. In the framework of tight binding (TB) model we calculate all the thermoelectric quantities using Landauer's prescription. The atypical and strange behavior of transmission function can be further modified by incorporating asymmetry in the hopping integrals of the SPG network. Here, we acquire a remarkably large value of thermoelectric efficiency from the system and we strongly believe that our work can be verified by a suitable experimental setup. The present analysis can easily be generalized in other similar kind of fractal lattices having multiple loops.