Hi Luk, I jump in. You can define, instead of the bond currents, something like a bond transmission. Such quantity, integrated on a plane, will give you the total transmission (a good sanity check). Therefore it will not depend on Vext and will be unitless. Some refers to it as transmission pathways.
I'm not familiar with Inelastica but from the formula this is what is calculated there. If you look in the supplementary material of the Nature Chemistry by G.Solomon you refer to in your first mail you can find something along those lines (see eq.11 in suppl.mat.). Anyway even though these object are very useful to get a physical insight, you should be a bit careful in giving a strict physical interpretation akin to current densities. As you see in the work from Todorov, these quantities are, differently from the total current, basis-dependent and therefore they are not uniquely defined. Best, Gabriele On 08/29/2016 08:09 PM, Luk Keh wrote: > Dear Nick, > > thanks for your reply, that paper was very insightful. I still have some > questions to get more understanding if you hopefully don't mind. So, in > the EigenChannels.py subroutine, the bond current for atoms (ij) is > calculated via 4 * pi * Im[H_ij * D_ji] where D is the DOS of the > considered electrode which is obtained by the resp. spectral function. > As I can see, this corresponds to eq. 100 or 101 (not sure here). In > both cases I don't see the prefactor G0 (G0*e) and for eq. 101, the > external bias Vext as prefactor misses too - which would yield zero bond > currents for Vext = 0. What I'm trying to understand is which unit the > bond currents have and why they exist for Vext = 0 which I tried out. > > Thanks alot and best regards, > Luk > > 2016-08-29 16:42 GMT+02:00 Nick Papior <nickpap...@gmail.com > <mailto:nickpap...@gmail.com>>: > > Sorry, it is the proxy used. > > Here: > http://dx.doi.org/10.1088/0953-8984/14/11/314 > <http://dx.doi.org/10.1088/0953-8984/14/11/314> > > 2016-08-29 16:30 GMT+02:00 Luk Keh <lukke...@gmail.com > <mailto:lukke...@gmail.com>>: > > Dear Nick, > > thanks for your instant reply. It seems that I need a login for > the link you provided. Can you provide another mirror or the > paper's title? > > Thanks alot, > Luk > > 2016-08-29 16:18 GMT+02:00 Nick Papior <nickpap...@gmail.com > <mailto:nickpap...@gmail.com>>: > > This paper is excellent in explaining the details concerning > bond-currents: > http://dx.doi.org.globalproxy.cvt.dk/10.1088/0953-8984/14/11/314 > <http://dx.doi.org.globalproxy.cvt.dk/10.1088/0953-8984/14/11/314> > > PS. In the next release of siesta, transiesta/tbtrans also > enables the calculation of bond-currents. > > 2016-08-29 16:11 GMT+02:00 Luk Keh <lukke...@gmail.com > <mailto:lukke...@gmail.com>>: > > Dear users and developers, > > could somebody tell me which unit the 'bond currents' in > the .curr files produced by Inelastica have? Are those > in fact transmissions (since they don't vanish without > bias, i.e. [f_L - f_R] = 0 => I_mn = 0) or actual > currents (in Ampere)? > Also I would like to know how those currents are > calculated. I found some papers, e.g. > http://www.nature.com/nchem/journal/v2/n3/full/nchem.546.html > > <http://www.nature.com/nchem/journal/v2/n3/full/nchem.546.html> > but I'm not sure about this. > > Thanks and best regards, > Luk > > > > > -- > Kind regards Nick > > > > > > -- > Kind regards Nick > > -- Gabriele Penazzi mobile: +49 (0) 151 19650383 skype: gabriele.penazzi
