kwant.builder.
InfiniteSystem
[source]¶Bases: kwant.system.InfiniteSystem
Finalized infinite system, extracted from a Builder
.
Notes
In infinite systems sites
consists of 3 parts: sites in the fundamental
domain (FD) with hoppings to neighboring cells, sites in the FD with no
hoppings to neighboring cells, and sites in FD+1 attached to the FD by
hoppings. Each of these three subsequences is individually sorted.
Attributes
sites  (sequence) sites[i] is the Site instance that corresponds to the integerlabeled site i of the lowlevel system. 
id_by_site  (dict) The inverse of sites ; maps from i to sites[i] . 
Methods
cell_hamiltonian
(args=(), sparse=False, *, params=None)[source]¶Hamiltonian of a single cell of the infinite system.
hamiltonian_submatrix
(self, args=(), to_sites=None, from_sites=None, sparse=False, return_norb=False, *, params=None)[source]¶Return a submatrix of the system Hamiltonian.
Parameters:  args : tuple, defaults to empty
to_sites : sequence of sites or None (default) from_sites : sequence of sites or None (default) sparse : bool
return_norb : bool
params : dict, optional


Returns:  hamiltonian_part : numpy.ndarray or scipy.sparse.coo_matrix
to_norb : array of integers
from_norb : array of integers

Notes
The returned submatrix contains all the Hamiltonian matrix elements
from from_sites
to to_sites
. The default for from_sites
and
to_sites
is None
which means to use all sites of the system in the
order in which they appear.
inter_cell_hopping
(args=(), sparse=False, *, params=None)[source]¶Hopping Hamiltonian between two cells of the infinite system.
modes
(energy=0, args=(), *, params=None)[source]¶Return mode decomposition of the lead
See documentation of PropagatingModes
and
StabilizedModes
for the return format details.
The wave functions of the returned modes are defined over the
unit cell of the system, which corresponds to the degrees of
freedom on the first cell_sites
sites of the system
(recall that infinite systems store first the sites in the unit
cell, then connected sites in the neighboring unit cell).