quantum-espresso/PP/simple_transport/README

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This is a collection of routines which compute transport coefficients
(Conductivity and Seebeck) using Boltzmann transport theory.
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Description of main programs:
* ef: Computation of Fermi Level for an insulating system with a given
doping level.
* dos: Computation of density of states using an adaptive smearing method.
Captures Van-Hove singularities better compared to constant
smearing.
* fermi_int_0: Computation of transport coefficients using constant
scattering rate and for a range of chemical potentials.
* fermi_int_1: Computation of transport coefficients using constant
scattering rate for a given Fermi Energy. Uses a
grid reduction algorithm (reducegrid.f90) to speed
up the transport integrals.
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Capabilities and things to do:
* The code uses finite differences to compute band velocities. For systems
with a fairly simple band structure, this poses no issue. For more
complicated with structures with lots of band crossings, finite
differences would fail. For such systems, use of packages like
BoltzTrap and Boltzwann are recommended.
* The code is not tested for spin-polarized systems and with k-point
grids that are not Gamma centered. It works for noncollinear
non-spin-polarized band structures.
* The code will be extended to include calculation of transport
integrals using model scattering rates.