Negative energy in exciton band structure including epc
Posted: Thu May 19, 2022 11:51 am
I want to interpolate hBN exciton band structure including electron-phonon coupling. However, I got negative energies on Q1 point as indicated by the tutorial website as:
Since the ypp only accept state range I think I can skip the negative energies and interpolated band 200-203, 210-213 separately. However, exciton energies is still negative on points other than Q1 and the interpolated bands are like:
Although I calculated the exciton eigenstates on 14 irreducible Q points. I can't get access to exciton energies on Q2 to Q14 using ypp_ph -e s. But I guess those negative energies appears due to the negative energy Q2 to Q14
How can I get rid of those unreasonable negative energies in finite temperature exciton band calculation.
Thanks
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-3.76358294 0.177910879E-4 219.000000 9.92491436
-3.75403833 0.755890869E-4 215.000000 10.0377493
-3.75096917 0.109721863E-3 207.000000 38.2221947
-3.74093676 0.100141997E-4 209.000000 33.6967010
-3.74088931 0.605661517E-4 208.000000 33.7033920
-3.54611969 0.986570299 184.000000 22.9587269
-3.54588223 0.309469014 185.000000 22.9632187
-3.52316475 0.617848360E-3 186.000000 28.0695610
-3.52294660 0.994357979E-3 187.000000 28.0626869
3.52295780 0.517361797E-3 202.000000 28.0637016
3.52316427 0.188250968E-3 203.000000 28.0689545
3.54586959 0.268980145 201.000000 22.9626389
3.54611135 1.00000000 200.000000 22.9591331
3.74088335 0.640694489E-4 213.000000 33.7050209
3.74091005 0.229923462E-4 212.000000 33.6954880
3.75101256 0.107493564E-3 211.000000 38.2237701
3.75404692 0.793393556E-4 210.000000 10.0376883
3.76359320 0.722822460E-5 217.000000 9.92613029
...
Code: Select all
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0.185671568 0.514611781 -4.12325191 -2.75979447 5.65440512 0.120689653 0.00000000 0.00000000
0.194513068 0.831551664E-2 -4.39890528 -3.12805891 5.57665730 0.126436785 0.00000000 0.00000000
0.203354567 -0.544920862 -4.62475967 -3.47219968 5.47007990 0.132183909 0.00000000 0.00000000
0.212196067 -1.14322174 -4.79626751 -3.78743505 5.33782244 0.137931034 0.00000000 0.00000000
0.221037567 -1.78390229 -4.90914202 -4.06907082 5.18379450 0.143678159 0.00000000 0.00000000
0.229879066 -2.46354914 -4.95943499 -4.31257296 5.01256466 0.149425283 0.00000000 0.00000000
0.238720581 -3.17809415 -4.94363499 -4.51362991 4.82924604 0.155172423 -0.745058060E-8 0.00000000
0.247562096 -3.92291451 -4.85873890 -4.66818857 4.63942480 0.160919562 -0.745058060E-8 0.00000000
0.256403595 -4.69292021 -4.70233393 -4.77248192 4.44907951 0.166666672 0.745058060E-8 0.00000000
0.265245110 -5.48265266 -4.47264099 -4.82302904 4.26454258 0.172413796 0.00000000 0.00000000
0.274086624 -6.28635073 -4.16855574 -4.81662846 4.09246349 0.178160921 0.745058060E-8 0.00000000
0.282928139 -7.09802675 -3.78966141 -4.75033188 3.93978453 0.183908060 -0.745058060E-8 0.00000000
0.291769654 -7.91152954 -3.33623362 -4.62144041 3.81369758 0.189655170 0.00000000 0.00000000
0.300611168 -8.72061920 -2.80921292 -4.42748451 3.72159219 0.195402309 0.00000000 0.00000000
0.309452683 -9.51899338 -2.21022105 -4.16625500 3.67096305 0.201149434 -0.745058060E-8 0.00000000
0.318294197 -10.3003855 -1.54151881 -3.83582401 3.66926694 0.206896558 0.00000000 0.00000000
0.327135712 -11.0585966 -0.806048512 -3.43462825 3.72373629 0.212643683 0.00000000 0.00000000
0.335977226 -11.7875948 -0.743483938E-2 -2.96156621 3.84113050 0.218390822 0.00000000 0.00000000
0.344818741 -12.4815664 0.849942625 -2.41611862 4.02744198 0.224137947 -0.745058060E-8 0.00000000
...
How can I get rid of those unreasonable negative energies in finite temperature exciton band calculation.
Thanks