SpinSite¶
full name: tenpy.networks.site.SpinSite
parent module:
tenpy.networks.site
type: class
Inheritance Diagram
Methods
|
Initialize self. |
|
Add one on-site operators. |
|
Change the charges of the site (in place). |
|
Load instance from a HDF5 file. |
|
Return the hermitian conjugate of a given operator. |
|
Return operator of given name. |
|
Multiply operator names together. |
|
Whether an (composite) onsite operator is fermionic and needs a Jordan-Wigner string. |
|
Remove an added operator. |
|
Rename an added operator. |
|
Export self into a HDF5 file. |
|
Return index of a basis state from its label. |
|
Same as |
Sanity check, raises ValueErrors, if something is wrong. |
|
|
Check whether ‘name’ labels a valid onsite-operator. |
Class Attributes and Properties
Dimension of the local Hilbert space. |
|
Dictionary of on-site operators for iteration. |
-
class
tenpy.networks.site.
SpinSite
(S=0.5, conserve='Sz')[source]¶ Bases:
tenpy.networks.site.Site
General Spin S site.
There are 2S+1 local states range from
down
(0) toup
(2S+1), corresponding toSz=-S, -S+1, ..., S-1, S
. Local operators are the spin-S operators, e.g.Sz = [[0.5, 0.], [0., -0.5]]
,Sx = 0.5*sigma_x
for the Pauli matrix sigma_x.operator
description
Id, JW
Identity \(\mathbb{1}\)
Sx, Sy, Sz
Spin components \(S^{x,y,z}\), equal to half the Pauli matrices.
Sp, Sm
Spin flips \(S^{\pm} = S^{x} \pm i S^{y}\)
conserve
qmod
excluded onsite operators
'Sz'
[1]
Sx, Sy
'parity'
[2]
–
None
[]
–
- Parameters
conserve (str) – Defines what is conserved, see table above.
-
S
¶ The 2S+1 states range from m = -S, -S+1, … +S.
- Type
{0.5, 1, 1.5, 2, ..}
-
add_op
(name, op, need_JW=False, hc=None)[source]¶ Add one on-site operators.
- Parameters
name (str) – A valid python variable name, used to label the operator. The name under which op is added as attribute to self.
op (np.ndarray |
Array
) – A matrix acting on the local hilbert space representing the local operator. Dense numpy arrays are automatically converted toArray
. LegCharges have to be[leg, leg.conj()]
. We set labels'p', 'p*'
.need_JW (bool) – Whether the operator needs a Jordan-Wigner string. If
True
, add name toneed_JW_string
.hc (None | False | str) – The name for the hermitian conjugate operator, to be used for
hc_ops
. By default (None
), try to auto-determine it. IfFalse
, disable adding antries tohc_ops
.
-
change_charge
(new_leg_charge=None, permute=None)[source]¶ Change the charges of the site (in place).
- Parameters
new_leg_charge (
LegCharge
| None) – The new charges to be used. IfNone
, use trivial charges.permute (ndarray | None) – The permuation applied to the physical leg, which gets used to adjust
state_labels
andperm
. If you sorted the previous leg withperm_qind, new_leg_charge = leg.sort()
, useold_leg.perm_flat_from_perm_qind(perm_qind)
. Ignored ifNone
.
-
property
dim
¶ Dimension of the local Hilbert space.
-
classmethod
from_hdf5
(hdf5_loader, h5gr, subpath)[source]¶ Load instance from a HDF5 file.
This method reconstructs a class instance from the data saved with
save_hdf5()
.
-
get_op
(name)[source]¶ Return operator of given name.
- Parameters
name (str) – The name of the operator to be returned. In case of multiple operator names separated by whitespace, we multiply them together to a single on-site operator (with the one on the right acting first).
- Returns
op – The operator given by name, with labels
'p', 'p*'
. If name already was an npc Array, it’s directly returned.- Return type
-
multiply_op_names
(names)[source]¶ Multiply operator names together.
Join the operator names in names such that get_op returns the product of the corresponding operators.
- Parameters
names (list of str) – List of valid operator labels.
- Returns
combined_opname – A valid operator name Operatorname representing the product of operators in names.
- Return type
-
property
onsite_ops
¶ Dictionary of on-site operators for iteration.
Single operators are accessible as attributes.
-
op_needs_JW
(name)[source]¶ Whether an (composite) onsite operator is fermionic and needs a Jordan-Wigner string.
-
remove_op
(name)[source]¶ Remove an added operator.
- Parameters
name (str) – The name of the operator to be removed.
-
save_hdf5
(hdf5_saver, h5gr, subpath)[source]¶ Export self into a HDF5 file.
This method saves all the data it needs to reconstruct self with
from_hdf5()
.This implementation saves the content of
__dict__
withsave_dict_content()
, storing the format under the attribute'format'
.
-
state_index
(label)[source]¶ Return index of a basis state from its label.
- Parameters
label (int | string) – eather the index directly or a label (string) set before.
- Returns
state_index – the index of the basis state associated with the label.
- Return type
-
state_indices
(labels)[source]¶ Same as
state_index()
, but for multiple labels.