Skip to main contentIBM Quantum Documentation
Important

IBM Quantum Platform is moving and this version will be sunset on July 1. To get started on the new platform, read the migration guide.

LayerModel

class LayerModel(model_params)

GitHub

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

Was this page helpful?
Report a bug or request content on GitHub.