qiskit.chemistry.components.variational_forms.UVCC¶

class UVCC(num_qubits, basis, degrees, reps=1, excitations=None, initial_state=None, qubit_mapping='direct', num_time_slices=1, shallow_circuit_concat=True)[source]¶

This trial wavefunction is a Unitary Vibrational Coupled-Cluster Single and Double excitations variational form. For more information, see Ollitrault Pauline J., Chemical science 11 (2020): 6842-6855.

Parameters

num_qubits (int) – number of qubits
basis (List[int]) – Is a list defining the number of modals per mode. E.g. for a 3 modes system with 4 modals per mode basis = [4,4,4]
degrees (List[int]) – degree of excitation to be included (for single and double excitations degrees=[0,1])
reps (int) – number of replica of basic module
excitations (Optional[List[List[List[int]]]]) – The excitations to be included in the circuit. If not provided the default is to compute all singles and doubles.
initial_state (Union[QuantumCircuit, InitialState, None]) – An initial state object.
qubit_mapping (str) – the qubits mapping type. Only ‘direct’ is supported at the moment.
num_time_slices (int) – parameters for dynamics.
shallow_circuit_concat (bool) – indicate whether to use shallow (cheap) mode for circuit concatenation

__init__(num_qubits, basis, degrees, reps=1, excitations=None, initial_state=None, qubit_mapping='direct', num_time_slices=1, shallow_circuit_concat=True)[source]¶

Parameters

num_qubits (int) – number of qubits
basis (List[int]) – Is a list defining the number of modals per mode. E.g. for a 3 modes system with 4 modals per mode basis = [4,4,4]
degrees (List[int]) – degree of excitation to be included (for single and double excitations degrees=[0,1])
reps (int) – number of replica of basic module
excitations (Optional[List[List[List[int]]]]) – The excitations to be included in the circuit. If not provided the default is to compute all singles and doubles.
initial_state (Union[QuantumCircuit, InitialState, None]) – An initial state object.
qubit_mapping (str) – the qubits mapping type. Only ‘direct’ is supported at the moment.
num_time_slices (int) – parameters for dynamics.
shallow_circuit_concat (bool) – indicate whether to use shallow (cheap) mode for circuit concatenation

Methods

`__init__`(num_qubits, basis, degrees[, reps, …])	type num_qubits `int`
`compute_excitation_lists`(basis, degrees)	Compute the list with all possible excitation for given orders
`construct_circuit`(parameters[, q])	Construct the variational form, given its parameters.
`excitations_in_qubit_format`()	Gives the list of excitation indexes in terms of qubit indexes rather
`get_entangler_map`(map_type, num_qubits[, offset])	returns entangler map
`validate_entangler_map`(entangler_map, num_qubits)	validate entangler map

Attributes

`num_parameters`	Number of parameters of the variational form.
`num_qubits`	Number of qubits of the variational form.
`parameter_bounds`	Parameter bounds.
`preferred_init_points`	Return preferred init points.
`setting`
`support_parameterized_circuit`	Whether or not the sub-class support parameterized circuit.

static compute_excitation_lists(basis, degrees)[source]¶

Compute the list with all possible excitation for given orders

Parameters

basis (List[int]) – Is a list defining the number of modals per mode. E.g. for a 3 modes system with 4 modals per mode basis = [4,4,4]
degrees (List[int]) – degree of excitation to be included (for single and double excitations degrees=[0,1])

Return type

List[List[int]]

Returns

List of excitation indexes in terms of modes and modals

Raises

ValueError – If excitation degree is greater than size of basis

construct_circuit(parameters, q=None)[source]¶

Construct the variational form, given its parameters.

Parameters

parameters (Union[ndarray, List[Parameter], ParameterVector]) – circuit parameters
q (Optional[QuantumRegister]) – Quantum Register for the circuit.

Return type

QuantumCircuit

Returns

Quantum Circuit a quantum circuit with given parameters

Raises

ValueError – the number of parameters is incorrect.
ValueError – if num_qubits has not been set and is still None

excitations_in_qubit_format()[source]¶

Gives the list of excitation indexes in terms of qubit indexes rather: than in modes and modals

Return type: List[List[int]]
Returns: List of excitation indexes

static get_entangler_map(map_type, num_qubits, offset=0)¶: returns entangler map

property num_parameters¶

Number of parameters of the variational form.

Returns: An integer indicating the number of parameters.
Return type: int

property num_qubits¶

Number of qubits of the variational form.

Returns: An integer indicating the number of qubits.
Return type: int

property parameter_bounds¶

Parameter bounds.

Returns: A list of pairs indicating the bounds, as (lower, upper). None indicates an unbounded parameter in the corresponding direction. If None is returned, problem is fully unbounded.
Return type: list

property preferred_init_points¶

Return preferred init points.

If an initial state is provided then the variational form may provide back this set of parameters which when used on the variational form should result in the overall state being that defined by the initial state

property setting¶

property support_parameterized_circuit¶

Whether or not the sub-class support parameterized circuit.

Returns: indicate the sub-class support parameterized circuit
Return type: boolean

static validate_entangler_map(entangler_map, num_qubits)¶: validate entangler map