Within the envelop-function framework, we propose a more efficient finite-element method to calculate the miniband structure and density of states in an idealistic nanocrystal array with realistic geometrical parameters. This method clearly reveals the miniband formation and accurately calculates the energy dispersion relationship. The calculated result agrees well with the analytical Kronig-Penney method. More importantly, this method surmounts the theoretical approximations of the multidimensional Kronig-Penney method, and provides significant information for 3-D quantum dots solar cell design by simulating an in-plane germanium nanodisk array in bulk silicon.
- Ge/Si quantum dot (QD)
- solar cell