— DEV — Modeling type-II superlattice using interface Hamiltonian within 8-band
Contents
- Files for the tutorial located in nextnano++\examples
T2SL_H-if_zb_III-V_Livneh_PRB_2012_1D_bandstructure.in (Figure 2.4.289)
T2SL_H-if_zb_III-V_Livneh_PRB_2012_1D_absorption.in (Figure 2.4.290)
- Parameters
$if_interface: 1 or 0, switches on and off the interface Hamiltonian$Nperiods: Number of periods in the superlattice.
- Output files
bias_00000\Quantum\Dispersions\dispersion_quantum_region_kp8_inplane_11_00_10.dat (Figure 2.4.289)
bias_00000\Quantum\Dispersions\dispersion_quantum_region_kp8_superlattice.dat (Figure 2.4.289)
bias_00000\OpticsQuantum\absorption_quantum_region_TE_y_nm.dat (Figure 2.4.290)
Introduction
This tutorial validates nextnano++ interface Hamiltonoian implementation with the results from [LivnehPRB2012]. The model and the implementation are described in detail in the Interface Hamiltonian 8-band Zinc-Blende section.
The objective is to calculate dispersion and optical properties of type-II InAs/GaSb superlattice.
The samples modeled are described in the table below, The thickness of the layers is expressed in monolayers (ML). In the original paper, the dispersion relation of sample 1 is given in figure 4, and the optical absorption of sample 2 is given in figure 6.
Parameter |
Sample 1 |
Sample 2 |
|---|---|---|
InAs thickness, ML |
13.8 |
8.7 |
GaSb thickness, ML |
7.8 |
10.6 |
Temperature, K |
77 |
77 |
Results
The disperson relation of the sample one is computed using the input file T2SL_H-if_zb_III-V_Livneh_PRB_2012_1D_bandstructure.in. For calculating dispersion, it is enough to include single period in the simulation. The dispersion relation is plotted in the figure below.
Figure 2.4.289 Dispersion relation of the sample 1, k-parallel dispersion on the left and superlattice dispersion on the right. Solid lines are nextnano++ results, dots represent data from [LivnehPRB2012].
The optical absorption of the sample two is computed using the input file T2SL_H-if_zb_III-V_Livneh_PRB_2012_1D_absorption.in. For adequat computation of the absorption in superlattice, few periods has to be included. In the figure below, 20 periods were fused in the computation.
Figure 2.4.290 Absorption coefficient calculated for the sample 2 with and without the interface (IF) Hamiltonian.
In the figure Figure 2.4.290, one can see the blue shift of the absorption edge with inclusion of the interface Hamiltonian.
Last update: 31/01/2025