LayerModel

class LayerModel(model_params)

Bases: CouplingMPOModel, NearestNeighborModel

A model for representing a layer of time-evolution interactions.

Essentially, this class is a simple wrapper of tenpy.models.model.CouplingMPOModel and tenpy.models.model.NearestNeighborModel. Its main purpose is to provide a simple interface for constructing a TeNPy-compatible Hamiltonian from Qiskit objects.

Methods

calc_H_bond

calc_H_bond(tol_zero=1e-15)

GitHub

Calculate the interaction Hamiltonian based on the coupling and onsite terms.

Essentially, this class overwrites calc_H_bond() and takes care of removing even or odd bond interaction Hamiltonians depending on the value of keep_only_odd (see tenpy_layers for more details).

Parameters

tol_zero (float) – the threshold for values considered to be zero.

Returns

The list of interaction Hamiltonians for all bonds.

Return type

list

from_quantum_circuit

classmethod from_quantum_circuit(circuit, **kwargs)

GitHub

Construct a LayerModel from a QuantumCircuit.

You can see an example of this function in action in the docs of tenpy_layers.

Note

By default, TeNPy tries to enforce spin-conservation and, thus, some operations may not be available. If you encounter an error stating that some operator (e.g. Sx) is not available, try specifying conserve="None". If that still does not work, converting your specific QuantumCircuit is currently not possible using this implementation.

Parameters

circuit (QuantumCircuit) – the quantum circuit to parse.
kwargs – any additional keyword arguments to pass to the LayerModel constructor.

Returns

A new LayerModel instance.

Raises

NotImplementedError – if an unsupported quantum gate is encountered.

Return type

LayerModel

init_sites

init_sites(model_params)

GitHub

Initializes the sites of this Hamiltonian.

See init_sites() for more details.

Parameters

model_params (Config) – the model parameters.

Returns

The site to be used internally.

Return type

Site

init_terms

init_terms(model_params)

GitHub

Initializes the terms of this Hamiltonian.

See init_terms() for more details.

Parameters

model_params (Config) – the model parameters.

Return type

None