An c++ software package aimed at quantum mechanics based atomistic simulation of semiconductor nanostructures using empirical tight binding model.
Executable file and input files examples are available by contacting the author by email yyyu200@163.com for trial usage.
Slater-Koster type sp3d5s* atomic basis semi-empirical parameters for main semiconductor materials;
1D, 2D and 3D periodic structures of nanostructures up to millions of atoms;
Electronic band structures, density of states projected to local atom orbitals.
Generate new tight binding parameters from simulated-annealing algorithm.
Calculation setup, parameters
k-points，support openmpi parallel calculation of k-points.
Unit cell and atomic positions, similar to POSCAR.
TB parameters.
Referential eigenvalues, only applicable in fitting mode(ISA=true). Usually get from DFT calculations, keep the same k-points mesh.
# NanoTB control tags '#' for comments
SYSTEM=TB #(optional)the name of the system.
LPRD = 1 1 1 # periodic boundary conditions 1 1 1 for the three dimensions
EAVE = 0.3 # (optional)Eigenvalue middle point
NCBAND = 40 # number of bands in eigenvalue calculation
SURFOFFSET = 5*0.18 # (optional) surface states
LBASIS = 1 1 1 1 5*1 1 # (optional)switch s p3 d5 s* default for 1
LSOI = 1 # spin-orbital interaction
#LHYDROGEN = 1 # pseudo-hydrogen(optional).
VERBOSITY= High
NMATE = 1 # species of materials
BONDLENGTH = 3.2800000 #bond length in Angstrom. Should consistent with pos.inp to set the hopping between neighbor atoms
MATFNAM=mat.inp # the filename of TB-parameters
ISA=false #whether fitting the TB parameters using simulated annealing algorithm (SA).
ITBOUT=true # whether to update output when doing SA. set to false when ISA=true.
#SA parameters (optional, only applicable when ISA=true)，See gsl manual (The GNU Scientific Library, http://www.gnu.org/software/gsl/)
N_TRIES=20 #
ITERS_FIXED_T=100
STEP_SIZE=1e-2
T_INITIAL=1e-3
T_MIN=1.0e-4
MU_T=1.108
# Add the weight of specific eigenvalues to the fitting object function. Can help to converge better to the desired eigenvalues.
FITK=6 0 # Add the weights of the sixth and the 0-th k-point, use with FITBAND
FITBAND=8 10 # Add the weights of the eighth and the tenth band of the sixth and the 0-th k-points.
FITGAP=0.19 4.128574 # help to fit the band gap at the k-points.
FITEIG=6 8 0.0 #help to fit the valence band maximum to 0.