Re: Transferred momenta and different LongDrXd orientation
Posted: Thu Mar 09, 2023 1:06 pm
Dear Davide,
we are sorry for the late reply but I was sick and then some family matters complicated my situation.
1) 'slab z':
We tested 'slab z' option without your patch (and with patch, initially) and it fixes the negative values problem.
Patch, no-patch, 'slab z' works fine; the patch does not affect the results both within and outside the 1st BZ.
Thank you very much for the hint.
The below plot displays the "bulk" ELF = Im{-1/eps} which confirms the many negative values of Im{eps} or Im{alpha} do not occur anymore. 2) Out of the 1st BZ:
We would like to calculate the 'alpha' and 'eps' for k-points outside of the 1st BZ along specific line-segments.
We would like to do this (more or less) equidistantly, already true within the 1st BZ.
Apart from line-segments containing Gamma, we would like to do this along the directions specified by M-L and K-H (in case of hexagonal cells).
Do you know of any easy way to set this up at the Yambo level?
Maybe, this is already implemented by an existing variable such as 'ShitedPaths'.
Our calculations within the 1st BZ along M-L and K-H show minimal variations (not displayed here) which is probably due to the z-component of the momentum being too small when compared to xy-components.
We expect that in sufficiently high order BZ, this may no longer be true.
Furthermore, the figure displaying ELF along Gamma-A direction exhibits a rather large gap in calculated distances from the Gamma-point.
There is a jump from 0.5 to 1.083 measured in iku units (see legend in the figure).
This means the calculated interval is not sampled equidistantly even though the initial k-points within the 1st BZ are equidistant.
Is there any symmetry to explain that this jump is only apparent (i.e. the segment Gamma-A is already equidistantly sampled)?
3) Information:
QDirection along the Gamma-A direction was not exactly preserved in some of our calculations along Gamma-A
Q(8) + G(17): 0.00000000 0.333333333E-1 8.00000000 [iku]
The 2nd coordinate deviates from expected zero values of both xy-components.
Is there any tolerance implemented?
Kind regards,
Martin
we are sorry for the late reply but I was sick and then some family matters complicated my situation.
1) 'slab z':
We tested 'slab z' option without your patch (and with patch, initially) and it fixes the negative values problem.
Patch, no-patch, 'slab z' works fine; the patch does not affect the results both within and outside the 1st BZ.
Thank you very much for the hint.
The below plot displays the "bulk" ELF = Im{-1/eps} which confirms the many negative values of Im{eps} or Im{alpha} do not occur anymore. 2) Out of the 1st BZ:
We would like to calculate the 'alpha' and 'eps' for k-points outside of the 1st BZ along specific line-segments.
We would like to do this (more or less) equidistantly, already true within the 1st BZ.
Apart from line-segments containing Gamma, we would like to do this along the directions specified by M-L and K-H (in case of hexagonal cells).
Do you know of any easy way to set this up at the Yambo level?
Maybe, this is already implemented by an existing variable such as 'ShitedPaths'.
Our calculations within the 1st BZ along M-L and K-H show minimal variations (not displayed here) which is probably due to the z-component of the momentum being too small when compared to xy-components.
We expect that in sufficiently high order BZ, this may no longer be true.
Furthermore, the figure displaying ELF along Gamma-A direction exhibits a rather large gap in calculated distances from the Gamma-point.
There is a jump from 0.5 to 1.083 measured in iku units (see legend in the figure).
This means the calculated interval is not sampled equidistantly even though the initial k-points within the 1st BZ are equidistant.
Is there any symmetry to explain that this jump is only apparent (i.e. the segment Gamma-A is already equidistantly sampled)?
3) Information:
QDirection along the Gamma-A direction was not exactly preserved in some of our calculations along Gamma-A
Q(8) + G(17): 0.00000000 0.333333333E-1 8.00000000 [iku]
The 2nd coordinate deviates from expected zero values of both xy-components.
Is there any tolerance implemented?
Kind regards,
Martin