4.1.1. tkwant.system.hamiltonian_with_boundaries

tkwant.system.hamiltonian_with_boundaries(syst, boundaries, params)[source]

Generate the Hamiltonian with boundary conditions attached.

Only generate the time-independent part of the Hamiltonian. The boundary conditions are represented by matrices \(h_n\) (one per lead) that will form a direct sum with the Hamiltonian of the central system, \(H_S\):

\[H_{tot} = H_S \oplus h_0 \oplus h_1 \oplus \cdots\]

In addition, coupling terms given by the lead inter-cell hoppings will be added between the added boundary conditions and the corresponding lead interface in the central system Hamiltonian.

Parameters

  • syst (FiniteSystem) – System with leads attached.

  • boundaries (sequence of BoundaryBase) – The boundary conditions to attach; one per lead.

  • params (dict, optional) – Extra arguments to pass to the Hamiltonian of syst at the initial time. Must include the time argument explicitly if Hamiltonian is time dependent.

Returns

The Hamiltonian of the central system, evaluated at t=0, with boundary conditions attached, and accompanying metadata.

Return type

ExtendedSystem