Dear Kwant user,Good day. I am notgetting the idea where and where not to use theconservation_lw=-sigma_z in spinful Hamiltonian. For instance in theTutorial 2.3.2. Spatially dependent values through functions, thehamiltanian is spinful but the conservation law was not set while computing the conductance. The same thing in the tutorial of Quantumanomalous Hall effect where the local current is plotted without highlighting the conservation law.

However, in the case of magnetic texture tutorial the conservation law was set as-sigma_z. Additionally, in some discussion ( kwant mailing list) about up/down conduction you have urged to set the conservation law to be-sigma_z instead of using two different lattices (up-lattice ansdown-lattice).
My question is why we have not used the conservation law in the first two examples.

In fact, I am calculating the current flow in a region where I have included some interactions such as intrinsic spin-orbit coupling, Rashba SOC and Pseudo inversion asymmetric SOC. So do I need to provide the type of conservation law or not.

Additionally, is there a way to calculate the current in parallel since the energy isone value. I mean the current for a given energy. So I am not getting the idea how to set parallel calculation in the case of current.

I do thank for your time and support

Regards

Adel BELAYADI