Hi,
In my understanding, a detailed calculation of the current carrying capacity is an extremely complicated task involving (i) electron-phonon coupling giving rise to current induced heating (i.e. energy transfer from the electrons to the phonon bath and vice versa); (ii) current-induced forces; (iii) this should be coupled with some kind of molecular dynamics simulation to actually model the break-down of the conductor.
Such a full calculation cannot be done with QuantumATK (or with any other tool as far as I am aware).
You can address parts of the problem individually such as electron-phonon coupling or to some extend current-induced forces (calculate the force at finite bias).
Regards,
Troels
