TBtrans (sisl.io.tbtrans)

File objects for interaction with the TBtrans code.

The TBtrans code is a tight-binding transport code implementing the widely used non-equilibrium Green function method.

It is primarily implemented for the support of TranSiesta (DFT+NEGF) as a backend for calculating transport for self-consistent DFT software.

Here we show a variety of supplement files that allows the extracting, manipulation and creation of files supported in TBtrans.

The basic file is the tbtncSileTBtrans which is a file to extract information from a TBtrans output file (typically named: siesta.TBT.nc). The following will interact with the TBtrans file:

>>> tbt = sisl.get_sile('siesta.TBT.nc')
>>> tbt.E
>>> tbt.a_d

Importantly one may retrieve quantities such as DOS, transmissions, transmission eigenvalues etc.

>>> tbt.transmission() # from electrode 0 -> 1 (default)
>>> tbt.transmission(0, 1) # from electrode 0 -> 1
>>> tbt.transmission(0, 2) # from electrode 0 -> 2
>>> tbt.ADOS(0, E=1.) # k-average, total spectral DOS from 0th electrode
>>> tbt.density_matrix(E=1.) # k-average, density matrix from Green function at 1. eV

The above extraction of data is the most frequent use of this module.

Data extraction files

• tbtncSileTBtrans (electron TBtrans output)

• tbtavncSileTBtrans (electron k-averaged TBtrans output)

• tbtsencSileTBtrans (electron TBtrans self-energy output)

• tbtprojncSileTBtrans (projected TBtrans output)

Support files to complement TBtrans

• deltancSileTBtrans adding \(\delta H\) or \(\delta\Sigma\) elements to a TBtrans calculation

• tbtgfSileTBtrans manual creation of the self-energies for TBtrans.

PHtrans

PHtrans is the same program as TBtrans, it however uses the dynamical matrix to calculate phonon transport.

• phtncSilePHtrans (phonon PHtrans output)

• phtsencSilePHtrans (phonon PHtrans self-energy output)

• phtavncSilePHtrans (phonon k-averaged PHtrans output)

• phtprojncSilePHtrans (projected PHtrans output)