Hi,
In the IV-Plot (see the 1.jpg in the attachment), one choice of the spin is "Z". Its meaning is unclear for me , and I have two questions.
1. What is the physical meaning of the choice Z? Is it about non-collinear (or non-collinear with spin orbit coupling) calculation?
2. In common spin-polarized (collinear) calculation, the 'Z' result is different from that of the 'sum, up or down'. I wonder why the difference occurs.
Thank you.