kwant.builder.
InfiniteVectorizedSystem
(builder, interface_order=None)[source]¶Bases: kwant.builder._VectorizedFinalizedBuilderMixin
, kwant.system.InfiniteVectorizedSystem
Finalized infinite system, extracted from a Builder
.
Notes
In infinite systems sites
and site_arrays
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.
SiteArray
The sites of the system.
sites[i]
is the Site
instance that corresponds
to the integer-labeled site i
of the low-level system.
The inverse of sites
; maps high-level Site
instances to their integer label.
Satisfies id_by_site[sites[i]] == i
.
Finalize a builder instance which has to have exactly a single symmetry direction.
If interface_order is not set, the order of the interface sites in the finalized system will be arbitrary. If interface_order is set to a sequence of interface sites, this order will be kept.
Methods
cell_hamiltonian
(args=(), sparse=False, *, params=None)[source]¶Hamiltonian of a single cell of the infinite system.
Providing positional arguments via ‘args’ is deprecated, instead, provide named parameters as a dictionary via ‘params’.
discrete_symmetry
(args=(), *, params=None)[source]¶Return the discrete symmetry of the system.
Providing positional arguments via ‘args’ is deprecated, instead, provide named parameters as a dictionary via ‘params’.
hamiltonian
(i, j, *args, params=None)[source]¶Return the hamiltonian matrix element for sites i
and j
.
If i == j
, return the on-site Hamiltonian of site i
.
if i != j
, return the hopping between site i
and j
.
Hamiltonians may depend (optionally) on positional and keyword arguments.
Providing positional arguments via ‘args’ is deprecated, instead, provide named parameters as a dictionary via ‘params’.
hamiltonian_submatrix
(args=(), sparse=False, return_norb=False, *, params=None)[source]¶Return The system Hamiltonian.
Positional arguments to pass to hamiltonian_term
. Mutually
exclusive with ‘params’.
Whether to return a sparse or a dense matrix. Defaults to False
.
Whether to return arrays of numbers of orbitals. Defaults to False
.
Dictionary of parameter names and their values. Mutually exclusive with ‘args’.
The Hamiltonian of the system.
Numbers of orbitals on each site. Only returned when return_norb
is true.
Notes
Providing positional arguments via ‘args’ is deprecated, instead, provide named parameters as a dictionary via ‘params’.
hamiltonian_term
(index, selector=slice(None, None, None), args=(), params=None)[source]¶Return the Hamiltonians for hamiltonian term number k.
The index of the term to evaluate.
The elements of the term to evaluate.
Positional arguments to the term. (Deprecated)
Keyword parameters to the term
Has shape (N, P, Q)
where N
is the number of matrix
elements in this term (or the number selected by ‘selector’
if provided), P
and Q
are the number of orbitals in the
‘to’ and ‘from’ site arrays associated with this term.
inter_cell_hopping
(args=(), sparse=False, *, params=None)[source]¶Hopping Hamiltonian between two cells of the infinite system.
This method returns a complex matrix that represents the hopping from
the interface sites of unit cell n - 1
to all the sites of
unit cell n
. It is therefore generally a rectangular matrix of
shape (N_uc, N_iface)
where N_uc
is the number of orbitals
in the unit cell, and N_iface
is the number of orbitals on the
interface sites (i.e. the sites with hoppings to the next unit cell).
Providing positional arguments via ‘args’ is deprecated, instead, provide named parameters as a dictionary via ‘params’.
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).
Providing positional arguments via ‘args’ is deprecated, instead, provide named parameters as a dictionary via ‘params’.
selfenergy
(energy=0, args=(), *, params=None)[source]¶Return self-energy of a lead.
The returned matrix has the shape (s, s), where s is
sum(len(self.hamiltonian(i, i)) for i in range(self.graph.num_nodes -
self.cell_size))
.
Providing positional arguments via ‘args’ is deprecated, instead, provide named parameters as a dictionary via ‘params’.
validate_symmetries
(args=(), *, params=None)[source]¶Check that the Hamiltonian satisfies discrete symmetries.
Returns validate
applied
to the onsite matrix and the hopping. See its documentation for
details on the return format.
Providing positional arguments via ‘args’ is deprecated, instead, provide named parameters as a dictionary via ‘params’.
Attributes