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Hi,
I want to plot the band structure for my system, i.e. a quantum dot. I am still confused as to what code I need to write to plot that, or whether sys.leads[0] is actually correct for what I need.
Calculating a band structure for a quantum dot is not mathematically well-defined. A quantum dot does not have translational symmetry, so momentum is not a good quantum number. You cannot label the eigenstates of your Hamiltonian with a unique momentum 'k', so plotting the associated eigenvalues as a function of 'k' (i.e. the band structure) is not possible. Even if you attach leads to your quantum dot you'll still have the same problem. While the leads *individually* have translational symmetry, the combination of leads and quantum dot does not, because the quantum dot breaks the translational symmetry. Given this, it is difficult for us to interpret what you mean when you say you want to plot "the band structure for your system". If you provide more context for what your end goal is, we may be able to help more. Happy Kwanting, Joe