Hex Lead Hamiltonians

  Copyright (C) 2009-2016 Peter Rakyta, Ph.D.
  This program is free software: you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.
  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.
  You should have received a copy of the GNU General Public License
  along with this program.  If not, see http://www.gnu.org/licenses/.

Description

Interface to create the Hamiltonian of one unit cell in a ribbon made of hexagonal lattice structure, including graphene and silicene.

Syntax

interface = Hex_Lead_Hamiltonians()

Methods (public)

Methods (protected)

Hex_Lead_Hamiltonians::Graphene_Bilayer_Lead_Hamiltonians

Description

Creates Hamiltonians H_0 and H_1 of bilayer graphene ribbon with zigzag/armchair edge as well as the structure conatining the coordinates of the atomic sites.

Syntax

[H0, H1, H1_transverse, coordinates] = object.Graphene_Bilayer_Lead_Hamiltonians(lead_param, M, End_Type, Atom_Type, varargin)

Parameters
lead_param An instance of structure lead_param containing the physical parameters of the ribbon.
M Number of sites in the cross section of the lead.
End_Type The type of the end of the ribbon ('A' for armchair or 'Z' for zigzag type end)
varargin Optional parameters given by a sequence ...'name', value,... . Possible parameters are:

  • q

    The tranverse momentum for transverse computations.

Return
H0 The Hamiltonian of one slab in the ribbon.
H1 The coupling between the slabs.
H1_transverse The transverse coupling between the slabs for transverse calculations.
coordinates A structure coordinates containing the coordinates of the sites.






Hex_Lead_Hamiltonians::Silicene_Lead_Hamiltonians

Description

Creates Hamiltonians H_0 and H_1 of silicene ribbon with zigzag edge as well as the structure conatining the coordinates of the atomic sites.

Syntax

[H0, H1, H1_transverse, coordinates] = object.Silicene_Lead_Hamiltonians(lead_param, M, End_Type, Atom_Type, varargin)

Parameters
lead_param An instance of structure lead_param containing the physical parameters of the ribbon.
M Number of sites in the cross section of the lead.
End_Type The type of the end of the ribbon ('A' for armchair or 'Z' for zigzag type end)
varargin Optional parameters given by a sequence ...'name', value,... . Possible parameters are:

  • q

    The tranverse momentum for transverse computations.

Return
H0 The Hamiltonian of one slab in the ribbon.
H1 The coupling between the slabs.
H1_transverse The transverse coupling between the slabs for transverse calculations.
coordinates A structure coordinates containing the coordinates of the sites.






Hex_Lead_Hamiltonians::Graphene_Lead_Hamiltonians

Description

Creates Hamiltonians H_0 and H_1 of single layer graphene ribbon with zigzag/armchair edge as well as the structure conatining the coordinates of the atomic sites.

Syntax

[H0, H1, H1_transverse, coordinates] = object.Graphene_Lead_Hamiltonians(lead_param, M, End_Type, Atom_Type, varargin)

Parameters
lead_param An instance of structure lead_param containing the physical parameters of the ribbon.
M Number of sites in the cross section of the lead.
End_Type The type of the end of the ribbon ('A' for armchair or 'Z' for zigzag type end)
varargin Optional parameters given by a sequence ...'name', value,... . Possible parameters are:

  • q

    The tranverse momentum for transverse computations.

Return
H0 The Hamiltonian of one slab in the ribbon.
H1 The coupling between the slabs.
H1_transverse The transverse coupling between the slabs for transverse calculations.
coordinates A structure coordinates containing the coordinates of the sites.






Hex_Lead_Hamiltonians::Armchair_End

Description

Creates Hamiltonians H_0 and H_1 of silicene ribbon with zigzag edge as well as the structure conatining the coordinates of the atomic sites.

Syntax

[H0, H1, H1_transverse, coordinates] = object.Armchair_End(epsilon,vargamma,M,q)

Parameters
epsilon The onsite potential.
vargamma The hopping amplitude.
M Number of sites in the cross section of the lead.
q The transverse momentum quantum number.

Return
H0 The Hamiltonian of one slab in the ribbon.
H1 The coupling between the slabs.
H1_transverse The transverse coupling between the slabs for transverse calculations.
coordinates A structure coordinates containing the coordinates of the sites.






Hex_Lead_Hamiltonians::Zigzag_End

Description

Creates Hamiltonians H_0 and H_1 of silicene ribbon with armchair edge as well as the structure conatining the coordinates of the atomic sites.

Syntax

[H0, H1, H1_transverse, coordinates] = object.Zigzag_End(epsilon,vargamma,M,q)

Parameters
epsilon The onsite potential.
vargamma The hopping amplitude.
M Number of sites in the cross section of the lead.
q The transverse momentum quantum number.

Return
H0 The Hamiltonian of one slab in the ribbon.
H1 The coupling between the slabs.
H1_transverse The transverse coupling between the slabs for transverse calculations.
coordinates A structure coordinates containing the coordinates of the sites.



Tags: 
hexagonal lattice
graphene
silicene
bilayer
interface

Comments

Submitted by Dávid Visontai on Mon, 11/16/2015 - 11:17.

would be useful to have a function that retrieves the wavefunctions for you. Not all of them of course, a bit like in the spectrum calculation, so around zero energy the first n. Thanks!