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Dear wien2k-users,<br>
<br>
There is a new<b> wien2wannier</b> version (0.96) available for
download at <br>
<br>
<a class="moz-txt-link-freetext" href="http://www.wien2k.at/reg_user/unsupported/wien2wannier">http://www.wien2k.at/reg_user/unsupported/wien2wannier</a><br>
<br>
Beside some bug-repairs, it includes the post-processing tool <b>woptic
</b>to compute the <b>optical conductivity</b>, dc-conductivity and
thermopower in the basis of Wannier functions computed by
wien2wannier.<br>
<br>
The main purpose of the algorithm is to compute these observables
employing a self energy sigma(w) from many-body calculations.<br>
<br>
Some features of woptic:<br>
1) It uses the wien2k momentum matrix elements(dipole matrix
elements) computed by optic rotated in the basis of Wannier
functions<br>
2) To include correlation effects one can use the self energy on the
real axis sigma(w) e.g. from DMFT calculations.<br>
3) It uses adaptive k-mesh refinement, i.e. in an iterative process,
the algorithm identifies regions in k-space where a larger portion
of the k-integration error comes from and resolves these regions
with a larger number of k-points thus decreasing the error.<br>
4) To compare with state-of-the-art LDA+DMFT, one can also use the
Peierls approximation instead of the full momentum matrices.<br>
5) One can also use the algorithm for pure LDA cases. It is,
however, often less efficient than optic-joint-kram. Since woptic
uses a direct linear response formula without a Kramers-Kronig
transform, it provides a good way to check the results.<br>
6) Optical transistions are not limited to the Wannier basis, but
one can also include transitions between the wien2k bands outside of
the wannier90 energy window and the Wannier orbitals (which are
usually adapted by correlation effects).<br>
<br>
Note that it is the first time that the full momentum matrix
elements are used in the LDA+DMFT framework. For results, computed
with woptic, see<br>
<br>
P. Wissgott, J. Kunes, A. Toschi and K. Held PRB 85, 205133 (2012)<br>
Dipole matrix element approach versus Peierls approximation for
optical conductivity<br>
<br>
For details on the usage see the wien2wannier userguide.<br>
<br>
For those of you who already downloaded wien2wannier at an earlier
stage: there is an old woptic version already included in the older
wien2wannier versions which was however rather buggy. This release
0.96 should therefore represent the first "official" version of
woptic.<br>
<br>
Best regards,<br>
Philipp Wissgott<br>
<br>
<br>
<pre class="moz-signature" cols="72">--
Philipp Wissgott
Institute for Solid State Physics, TU Wien
phone ++43 1 58801 13769
<a class="moz-txt-link-abbreviated" href="mailto:wissgott@ifp.tuwien.ac.at">wissgott@ifp.tuwien.ac.at</a>
<a class="moz-txt-link-freetext" href="http://www.ifp.tuwien.ac.at/cms">http://www.ifp.tuwien.ac.at/cms</a>
</pre>
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