Silicon: Spin-Orbit Coupling

Run qe2pert.x and perturbo.x on silicon with spin-orbit coupling

The input files can be found in the directory “pw-ph-wann”. Remember to run scf, nscf and Wannier90 calculations that include spinor-related variables. Once the DFT and DFPT calculations are completed, we run qe2pert.x to generate ‘prefix’_epr.h5. In the input file for qe2pert.x (“qe2pert/pert.in”) the user does not need to specify any spinor-related variables since qe2pert.x is able to detect that spin-orbit coupling (SOC) was used in DFT. Here is the input file (pert.in):

&qe2pert
 prefix='si'
 outdir='./tmp'
 phdir='../pw-ph-wann/phonon/References/save'
 nk1=8, nk2=8, nk3=8
 dft_band_min = 1
 dft_band_max = 32
 num_wann = 16
 lwannier=.true.
/

The input file is similar to the one for silicon without SOC (“example02-silicon-qe2pert”, link). We only need to double the number of Wannier functions (num_wann variable) and DFT bands (dft_band_min and dft_band_max) in the input file.

The input files for perturbo.x are also similar to the silicon calculations without SOC, except for the band range given by dft_band_min and dft_band_max. Each calculation is the same as in the silicon example without SOC.