Bozidar Novakovic

Objective:

• Energy grid with optimal size.
• As few relevant energies with sufficient resolution as possible.
• Relevant energies contribute most to charge density based on wave function normalization and Fermi-Dirac distribution.

Approach:

• Lead band structure: density of states peaks are near band minima.
• Include more energy points around band minima to resolve DOS peaks and less elsewhere to speed up computation.

Results:

• Energy grid (top panel) is denser around band extrema (bottom panel).

Acknowledgment: OMEN code.

Example: GaAs nanowire in effective mass.

Impact:

• Robust convergence of Poisson and transport equations by consistently including relevant energies in all iterations.

Publications:

• As a basic algorithm used in many works, for example:
  1. Journal of Computational Electronics, Dec. 2013, vol. 12, iss. 4, pp 592-600. doi:10.1007/s10825-013-0509-0
  2. IEEE Electron Device Lett., vol. 35, pp. 1212-1214, Dec. 2014. doi:10.1109/LED.2014.2364593
  3. IEEE Journal on Exploratory Solid-State Computational Devices and Circuits, vol. 1, pp. 12-18, Apr. 2015. doi:10.1109/JXCDC.2015.2423096

Adaptive grid easily outperforms simple homogeneous grid by having much smaller convergence residual.