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! Copyright (C) 1996-2016 The SIESTA group
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! This file is distributed under the terms of the
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! GNU General Public License: see COPYING in the top directory
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! or http://www.gnu.org/copyleft/gpl.txt .
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! See Docs/Contributors.txt for a list of contributors.
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! This code has been fully implemented by:
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! Please attribute the original author in case of dublication
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! Enable the feature of manipulating with the
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! Hamiltonian from outside.
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! This is easily done by letting the user
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! create a NetCDF file which contain dSE elements
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! which will enter the NEGF equations through:
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! We note that the user can input several different
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! corresponding to different situations.
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! If dSE is complex, one can use dSE as an onsite
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! self-energy change, thus introducing spurious
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! The dSE is effectively a change in the self-energies and
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! will thus NOT enter in the equations for the bond-currents.
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! If one has a dSE term that should contribute to the bond-currents
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! please look at m_tbt_dH.F90.
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! There are 4 levels of usage:
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! This will enter in a common equation
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! This will only enter for the corresponding
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! H_k = H_k + dSE_k' with dSE_k' = 0 for k/=k'
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! This will as 2. only enter for specific
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! H(E) = H(E) + dSE(E') with dSE(E') = 0 for E/=E'
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! 4. k and E dependent dSE
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! H_k(E) = H_k(E) + dSE_k'(E') with dSE_k'(E') = 0 for E/=E' and k/=k'
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! Note that the highest level has precedence above the others,
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! so specifying both 1. and 4. will only be the equivalent of
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! This is particularly handy for TB calculations
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! but can prove just as useful for regular DFT
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! calculations as one can use an already existing
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! SIESTA.nc file, and then do several "case" studies
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! on such a file, thus actually having FULL control
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use m_tbt_delta, only: tDelta
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! The dSE global variable
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type(tDelta), save :: dSE
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! Whether this is used or not
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logical :: use_dSE = .false.
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public :: dSE, use_dSE
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public :: init_dSE_options, print_dSE_options
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subroutine init_dSE_options( )
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use m_tbt_delta, only: init_delta_options, delta_has_level
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call init_delta_options('dSE', dSE)
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use_dSE = use_dSE .or. delta_has_level(dSE, i)
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end subroutine init_dSE_options
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subroutine print_dSE_options( )
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use parallel, only : IONode
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character(len=*), parameter :: f10='(''tbt: '',a,t53,''='',tr4,a)'
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character(len=*), parameter :: f11='(''tbt: '',a)'
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character(len=*), parameter :: f1 ='(''tbt: '',a,t53,''='',tr4,l1)'
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if ( .not. IONode ) return
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if ( len_trim(dSE%fname) == 0 ) then
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write(*,f11)'No delta self-energy'
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write(*,f10)'User selected dSE file', trim(dSE%fname)
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write(*,f11)'delta self-energy cannot be used (requires NetCDF4)'
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end subroutine print_dSE_options
added
removed
Util/TS/TBtrans/m_tbt_dSE.F90
