Favago Transport Programming Interface

Introduction

Interfaces

Data structures

Examples







Data structures

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Description

Description of data structures used in Favago Transport Programming Interface

param

Fields
scatter An instance of the structure scatter_param containing the physical parameters for the scattering region.
Leads A list of structures Lead_param containing the physical parameters for the scattering region.



scatter_param

Fields
epsilon On-site energy in the scattering region.
vargamma The hopping amplitude in the scattering region.
SOintrinsic strength of the intrinsic SOI in silicene.
deltaAB The strength of the staggered A-B potential in silicene.
SO_rashba_intrinsic The strength of the intrinsic Rashba SOI in silicene.
vargamma1 The strength of the interlayer hopping in bilayer graphene-like materials.
vargamma3 The strength of the warping hopping in bilayer graphene-like materials.
pair_potential The pair potential for superconducting phases (a complex number).
Overlap_in_Scatter Logical parameter. Set true to use overlap integrals in the scattering center, false otherwise.
shape An instance of structure shape.
End_Type Values are 'A' for zigzag edged ribbon (Armchair end), and 'Z' for ribbon with armchair type edges (Zigzag end) in hexagonal lattice.



lead_param

Fields
epsilon On-site energy in the lead.
vargamma The hopping amplitude in the lead.
SOintrinsic strength of the intrinsic SOI in silicene.
deltaAB The strength of the staggered A-B potential in silicene.
SO_rashba_intrinsic The strength of the intrinsic Rashba SOI in silicene.
vargamma1 The strength of the interlayer hopping in bilayer graphene-like materials.
vargamma3 The strength of the warping hopping in bilayer graphene-like materials.
pair_potential The pair potential for superconducting phases (complex number).
Overlap_in_Lead Logical parameter. Set true to use overlap integrals in the lead, false otherwise.
orientation Set $+1$ if the in-comming states to the scattering center are propagating in the $+x$ or $+y$ direction, and $-1$ otherwise.
M The number of the sites in the cross section of the lead.
End_Type Values are 'A' for zigzag edged ribbon (Armchair end), and 'Z' for ribbon with armchair type edges (Zigzag end) in hexagonal lattice.



Opt

Fields
Hscatter set 1 to load the Hamiltonian of the scattering region from a file, 0 otherwise.
Hleads set 1 to load the Hamiltonian of the leads from a file, 0 otherwise.
Decimation Option for using decimation. Type 1,2 or 3 to use it, 0 to not use it. (see more details at Decimation)
Decimation_block The maximal number of the sites to be decimated at once.
Decimate_only_Dyson Set 1 for decimate only the Dyson equation, and 0 otherwise. (has effect only if Decimation>0) --- Obsolete
NofLeads Number of leads attached to the scattering region.
Potential Set 1 to use extra electric potential, 0 otherwise. --- Obsolete
magnetic_field Set 1 if a magnetic field is involved in the calculations, 0 otherwise.
Lattice_Type Set 'S' for square lattice, 'H' for graphene lattice, 'Silicene' for Silicene.
Simple_Green_Function Set 1 if a simple analytical surface greens function computational method is about to be used, 0 otherwise.
Linear_Regression_in_B Set 1 for using linear regression to calculate the Peierls integrals between the sites. Useful when dealing with a homogeneous magnetic field.
Just_Create_Hamiltonians set 1 for calculating only the Hamiltonians with the Peierls phases. --- Obsolete
saveWithMagneticFiled Obsolete
BdG Set 1 for superconducting systems, 0 (default) for normal systems
Silent Set 1 in order to mute the output messages.
usingDualModes Set 1 to use dual modes in the calculations, or 0 to use the left and right sided eigenvectors instead.
debug Set 1 to export debug informations into the debug.txt file, or 0 otherwise.



coordinates

Fields
x A vector containing the $x$ coordinates of the sites.
y A vector containing the $y$ coordinates of the sites.
z A vector containing the $z$ coordinates of the sites.
a The lattice vector of the lead.
spinup Vector of logicals. Used in system including a spin degree of freedom. Values "true" gives sites with spin up, and values "false" stand for the spin down sites.
BdG_u Vector of logicals. Used in the Bogoliubov de Gennes Hamiltonians. Values "true" gives sites corresponding to the "u" component of the wave function, and values "false" stand for the sites of the "v" component of the wave function.



shape

Fields
width The number of sites in the cross section.
height Number of (ribbon) unit cells in the scattering region.
Atom_Type The type of the first site at the position (1,1) of the Hamiltonian in a hexagonal lattice (values are 'A' or 'B')



hole

Fields
center A vector $$[x,y]$$ containing the coordinates of the center.
radius The radius of the hole in the units of the lattice constant.



scatterers

Fields
z A vector of slab indexes in the ribbon.
zpoints A vector of site indexes in the slabs.
potentials A vector of the on-site potentials.
siteindexes A vector of the site indexes (generated from $$z$$ and $$zpoints$$)
aremissing Set true if the given sites are about to remove from the lattice.



BandWidth

Fields
Lead An instance of the structure BandWidtLimits for the lead.
Scatter An instance of the structure BandWidtLimits for the scattering region.



BandWidthLimits

Fields
Emin The minimal value of the energy band.
Emax The maximal value of the energy band.