qiskit.chemistry.components.variational_forms.CHC

class CHC(num_qubits=None, reps=1, ladder=False, excitations=None, entanglement='full', initial_state=None)

This trial wavefunction is the Compact Heuristic for Chemistry.

The trial wavefunction is as defined in Ollitrault Pauline J., Chemical science 11 (2020): 6842-6855. It aims at approximating the UCC Ansatz for a lower CNOT count.

注釈

It is not particle number conserving and the accuracy of the approximation decreases with the number of excitations.

パラメータ

• num_qubits (Optional[int]) – number of qubits

• reps (int) – number of replica of basic module

• ladder (bool) – use ladder of CNOTs between to indices in the entangling block

• excitations (Optional[List[List[int]]]) – indices corresponding to the excitations to include in the circuit

• entanglement (Union[str, List[int]]) – physical connections between the qubits

• initial_state (Union[QuantumCircuit, InitialState, None]) – an initial state to prepend to the variational form

__init__(num_qubits=None, reps=1, ladder=False, excitations=None, entanglement='full', initial_state=None)

パラメータ

• num_qubits (Optional[int]) – number of qubits

• reps (int) – number of replica of basic module

• ladder (bool) – use ladder of CNOTs between to indices in the entangling block

• excitations (Optional[List[List[int]]]) – indices corresponding to the excitations to include in the circuit

• entanglement (Union[str, List[int]]) – physical connections between the qubits

• initial_state (Union[QuantumCircuit, InitialState, None]) – an initial state to prepend to the variational form

Methods

__init__([num_qubits, reps, ladder, …])	type num_qubits Optional[int]
construct_circuit(parameters[, q])	Construct the variational form, given its parameters.
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.

construct_circuit(parameters, q=None)

Construct the variational form, given its parameters.

パラメータ

• parameters (Union[ndarray, List[Parameter], ParameterVector]) – circuit parameters

• q (Optional[QuantumRegister]) – Quantum Register for the circuit.

戻り値

a quantum circuit with given parameters

戻り値の型

QuantumCircuit

例外

• ValueError – the number of parameters is incorrect.

• ValueError – if num_qubits has not been set and is still None

• ValueError – only supports single and double excitations at the moment.

static get_entangler_map(map_type, num_qubits, offset=0)

returns entangler map

property num_parameters

Number of parameters of the variational form.

戻り値

An integer indicating the number of parameters.

戻り値の型

int

property num_qubits

Number of qubits of the variational form.

戻り値

An integer indicating the number of qubits.

戻り値の型

int

property parameter_bounds

Parameter bounds.

戻り値

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.

戻り値の型

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.

戻り値

indicate the sub-class support parameterized circuit

戻り値の型

boolean

static validate_entangler_map(entangler_map, num_qubits)

validate entangler map