335 lines
16 KiB
Plaintext
335 lines
16 KiB
Plaintext
---
|
||
title: EfficientSU2
|
||
description: API reference for qiskit.circuit.library.EfficientSU2
|
||
in_page_toc_min_heading_level: 1
|
||
python_api_type: class
|
||
python_api_name: qiskit.circuit.library.EfficientSU2
|
||
---
|
||
|
||
# EfficientSU2
|
||
|
||
<Class id="qiskit.circuit.library.EfficientSU2" isDedicatedPage={true} github="https://github.com/qiskit/qiskit/tree/stable/0.24/qiskit/circuit/library/n_local/efficient_su2.py" signature="EfficientSU2(num_qubits=None, su2_gates=None, entanglement='reverse_linear', reps=3, skip_unentangled_qubits=False, skip_final_rotation_layer=False, parameter_prefix='θ', insert_barriers=False, initial_state=None, name='EfficientSU2')" modifiers="class">
|
||
Bases: [`TwoLocal`](qiskit.circuit.library.TwoLocal "qiskit.circuit.library.n_local.two_local.TwoLocal")
|
||
|
||
The hardware efficient SU(2) 2-local circuit.
|
||
|
||
The `EfficientSU2` circuit consists of layers of single qubit operations spanned by SU(2) and $CX$ entanglements. This is a heuristic pattern that can be used to prepare trial wave functions for variational quantum algorithms or classification circuit for machine learning.
|
||
|
||
SU(2) stands for special unitary group of degree 2, its elements are $2 \times 2$ unitary matrices with determinant 1, such as the Pauli rotation gates.
|
||
|
||
On 3 qubits and using the Pauli $Y$ and $Z$ su2\_gates as single qubit gates, the hardware efficient SU(2) circuit is represented by:
|
||
|
||
```python
|
||
┌──────────┐┌──────────┐ ░ ░ ░ ┌───────────┐┌───────────┐
|
||
┤ RY(θ[0]) ├┤ RZ(θ[3]) ├─░────────■───░─ ... ─░─┤ RY(θ[12]) ├┤ RZ(θ[15]) ├
|
||
├──────────┤├──────────┤ ░ ┌─┴─┐ ░ ░ ├───────────┤├───────────┤
|
||
┤ RY(θ[1]) ├┤ RZ(θ[4]) ├─░───■──┤ X ├─░─ ... ─░─┤ RY(θ[13]) ├┤ RZ(θ[16]) ├
|
||
├──────────┤├──────────┤ ░ ┌─┴─┐└───┘ ░ ░ ├───────────┤├───────────┤
|
||
┤ RY(θ[2]) ├┤ RZ(θ[5]) ├─░─┤ X ├──────░─ ... ─░─┤ RY(θ[14]) ├┤ RZ(θ[17]) ├
|
||
└──────────┘└──────────┘ ░ └───┘ ░ ░ └───────────┘└───────────┘
|
||
```
|
||
|
||
See [`RealAmplitudes`](qiskit.circuit.library.RealAmplitudes "qiskit.circuit.library.RealAmplitudes") for more detail on the possible arguments and options such as skipping unentanglement qubits, which apply here too.
|
||
|
||
**Examples**
|
||
|
||
```python
|
||
>>> circuit = EfficientSU2(3, reps=1)
|
||
>>> print(circuit)
|
||
┌──────────┐┌──────────┐ ┌──────────┐┌──────────┐
|
||
q_0: ┤ RY(θ[0]) ├┤ RZ(θ[3]) ├──■────■──┤ RY(θ[6]) ├┤ RZ(θ[9]) ├─────────────
|
||
├──────────┤├──────────┤┌─┴─┐ │ └──────────┘├──────────┤┌───────────┐
|
||
q_1: ┤ RY(θ[1]) ├┤ RZ(θ[4]) ├┤ X ├──┼───────■──────┤ RY(θ[7]) ├┤ RZ(θ[10]) ├
|
||
├──────────┤├──────────┤└───┘┌─┴─┐ ┌─┴─┐ ├──────────┤├───────────┤
|
||
q_2: ┤ RY(θ[2]) ├┤ RZ(θ[5]) ├─────┤ X ├───┤ X ├────┤ RY(θ[8]) ├┤ RZ(θ[11]) ├
|
||
└──────────┘└──────────┘ └───┘ └───┘ └──────────┘└───────────┘
|
||
```
|
||
|
||
```python
|
||
>>> ansatz = EfficientSU2(4, su2_gates=['rx', 'y'], entanglement='circular', reps=1)
|
||
>>> qc = QuantumCircuit(4) # create a circuit and append the RY variational form
|
||
>>> qc.compose(ansatz, inplace=True)
|
||
>>> qc.draw()
|
||
┌──────────┐┌───┐┌───┐ ┌──────────┐ ┌───┐
|
||
q_0: ┤ RX(θ[0]) ├┤ Y ├┤ X ├──■──┤ RX(θ[4]) ├───┤ Y ├─────────────────────
|
||
├──────────┤├───┤└─┬─┘┌─┴─┐└──────────┘┌──┴───┴───┐ ┌───┐
|
||
q_1: ┤ RX(θ[1]) ├┤ Y ├──┼──┤ X ├─────■──────┤ RX(θ[5]) ├───┤ Y ├─────────
|
||
├──────────┤├───┤ │ └───┘ ┌─┴─┐ └──────────┘┌──┴───┴───┐┌───┐
|
||
q_2: ┤ RX(θ[2]) ├┤ Y ├──┼──────────┤ X ├─────────■──────┤ RX(θ[6]) ├┤ Y ├
|
||
├──────────┤├───┤ │ └───┘ ┌─┴─┐ ├──────────┤├───┤
|
||
q_3: ┤ RX(θ[3]) ├┤ Y ├──■──────────────────────┤ X ├────┤ RX(θ[7]) ├┤ Y ├
|
||
└──────────┘└───┘ └───┘ └──────────┘└───┘
|
||
```
|
||
|
||
Create a new EfficientSU2 2-local circuit.
|
||
|
||
**Parameters**
|
||
|
||
* **num\_qubits** (*int | None*) – The number of qubits of the EfficientSU2 circuit.
|
||
* **reps** (*int*) – Specifies how often the structure of a rotation layer followed by an entanglement layer is repeated.
|
||
* **su2\_gates** (*str | type |* [*Instruction*](qiskit.circuit.Instruction "qiskit.circuit.instruction.Instruction") *|*[*QuantumCircuit*](qiskit.circuit.QuantumCircuit "qiskit.circuit.quantumcircuit.QuantumCircuit") *| List\[str | type |*[*Instruction*](qiskit.circuit.Instruction "qiskit.circuit.instruction.Instruction") *|*[*QuantumCircuit*](qiskit.circuit.QuantumCircuit "qiskit.circuit.quantumcircuit.QuantumCircuit")*] | None*) – The SU(2) single qubit gates to apply in single qubit gate layers. If only one gate is provided, the same gate is applied to each qubit. If a list of gates is provided, all gates are applied to each qubit in the provided order.
|
||
* **entanglement** (*str | List\[List\[int]] | Callable\[\[int], List\[int]]*) – Specifies the entanglement structure. Can be a string (‘full’, ‘linear’ , ‘reverse\_linear’, ‘circular’ or ‘sca’), a list of integer-pairs specifying the indices of qubits entangled with one another, or a callable returning such a list provided with the index of the entanglement layer. Default to ‘reverse\_linear’ entanglement. Note that ‘reverse\_linear’ entanglement provides the same unitary as ‘full’ with fewer entangling gates. See the Examples section of [`TwoLocal`](qiskit.circuit.library.TwoLocal "qiskit.circuit.library.TwoLocal") for more detail.
|
||
* **initial\_state** (*Any | None*) – A QuantumCircuit object to prepend to the circuit.
|
||
* **skip\_unentangled\_qubits** (*bool*) – If True, the single qubit gates are only applied to qubits that are entangled with another qubit. If False, the single qubit gates are applied to each qubit in the Ansatz. Defaults to False.
|
||
* **skip\_final\_rotation\_layer** (*bool*) – If False, a rotation layer is added at the end of the ansatz. If True, no rotation layer is added.
|
||
* **parameter\_prefix** (*str*) – The parameterized gates require a parameter to be defined, for which we use [`ParameterVector`](qiskit.circuit.ParameterVector "qiskit.circuit.ParameterVector").
|
||
* **insert\_barriers** (*bool*) – If True, barriers are inserted in between each layer. If False, no barriers are inserted.
|
||
|
||
## Attributes
|
||
|
||
### ancillas
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.ancillas">
|
||
Returns a list of ancilla bits in the order that the registers were added.
|
||
</Attribute>
|
||
|
||
### calibrations
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.calibrations">
|
||
Return calibration dictionary.
|
||
|
||
The custom pulse definition of a given gate is of the form `{'gate_name': {(qubits, params): schedule}}`
|
||
</Attribute>
|
||
|
||
### clbits
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.clbits">
|
||
Returns a list of classical bits in the order that the registers were added.
|
||
</Attribute>
|
||
|
||
### data
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.data" />
|
||
|
||
### entanglement
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.entanglement">
|
||
Get the entanglement strategy.
|
||
|
||
**Returns**
|
||
|
||
The entanglement strategy, see `get_entangler_map()` for more detail on how the format is interpreted.
|
||
</Attribute>
|
||
|
||
### entanglement\_blocks
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.entanglement_blocks">
|
||
The blocks in the entanglement layers.
|
||
|
||
**Returns**
|
||
|
||
The blocks in the entanglement layers.
|
||
</Attribute>
|
||
|
||
### extension\_lib
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.extension_lib" attributeValue="'include "qelib1.inc";'" />
|
||
|
||
### global\_phase
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.global_phase">
|
||
Return the global phase of the circuit in radians.
|
||
</Attribute>
|
||
|
||
### header
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.header" attributeValue="'OPENQASM 2.0;'" />
|
||
|
||
### initial\_state
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.initial_state">
|
||
Return the initial state that is added in front of the n-local circuit.
|
||
|
||
**Returns**
|
||
|
||
The initial state.
|
||
</Attribute>
|
||
|
||
### insert\_barriers
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.insert_barriers">
|
||
If barriers are inserted in between the layers or not.
|
||
|
||
**Returns**
|
||
|
||
`True`, if barriers are inserted in between the layers, `False` if not.
|
||
</Attribute>
|
||
|
||
### instances
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.instances" attributeValue="121" />
|
||
|
||
### layout
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.layout">
|
||
Return any associated layout information anout the circuit
|
||
|
||
This attribute contains an optional [`TranspileLayout`](qiskit.transpiler.TranspileLayout "qiskit.transpiler.TranspileLayout") object. This is typically set on the output from [`transpile()`](qiskit.compiler.transpile "qiskit.compiler.transpile") or [`PassManager.run()`](qiskit.transpiler.PassManager#run "qiskit.transpiler.PassManager.run") to retain information about the permutations caused on the input circuit by transpilation.
|
||
|
||
There are two types of permutations caused by the [`transpile()`](qiskit.compiler.transpile "qiskit.compiler.transpile") function, an initial layout which permutes the qubits based on the selected physical qubits on the [`Target`](qiskit.transpiler.Target "qiskit.transpiler.Target"), and a final layout which is an output permutation caused by [`SwapGate`](qiskit.circuit.library.SwapGate "qiskit.circuit.library.SwapGate")s inserted during routing.
|
||
</Attribute>
|
||
|
||
### metadata
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.metadata">
|
||
The user provided metadata associated with the circuit.
|
||
|
||
The metadata for the circuit is a user provided `dict` of metadata for the circuit. It will not be used to influence the execution or operation of the circuit, but it is expected to be passed between all transforms of the circuit (ie transpilation) and that providers will associate any circuit metadata with the results it returns from execution of that circuit.
|
||
</Attribute>
|
||
|
||
### num\_ancillas
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.num_ancillas">
|
||
Return the number of ancilla qubits.
|
||
</Attribute>
|
||
|
||
### num\_clbits
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.num_clbits">
|
||
Return number of classical bits.
|
||
</Attribute>
|
||
|
||
### num\_layers
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.num_layers">
|
||
Return the number of layers in the n-local circuit.
|
||
|
||
**Returns**
|
||
|
||
The number of layers in the circuit.
|
||
</Attribute>
|
||
|
||
### num\_parameters
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.num_parameters" />
|
||
|
||
### num\_parameters\_settable
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.num_parameters_settable">
|
||
The number of total parameters that can be set to distinct values.
|
||
|
||
This does not change when the parameters are bound or exchanged for same parameters, and therefore is different from `num_parameters` which counts the number of unique [`Parameter`](qiskit.circuit.Parameter "qiskit.circuit.Parameter") objects currently in the circuit.
|
||
|
||
**Returns**
|
||
|
||
The number of parameters originally available in the circuit.
|
||
|
||
<Admonition title="Note" type="note">
|
||
This quantity does not require the circuit to be built yet.
|
||
</Admonition>
|
||
</Attribute>
|
||
|
||
### num\_qubits
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.num_qubits">
|
||
Returns the number of qubits in this circuit.
|
||
|
||
**Returns**
|
||
|
||
The number of qubits.
|
||
</Attribute>
|
||
|
||
### op\_start\_times
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.op_start_times">
|
||
Return a list of operation start times.
|
||
|
||
This attribute is enabled once one of scheduling analysis passes runs on the quantum circuit.
|
||
|
||
**Returns**
|
||
|
||
List of integers representing instruction start times. The index corresponds to the index of instruction in `QuantumCircuit.data`.
|
||
|
||
**Raises**
|
||
|
||
**AttributeError** – When circuit is not scheduled.
|
||
</Attribute>
|
||
|
||
### ordered\_parameters
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.ordered_parameters">
|
||
The parameters used in the underlying circuit.
|
||
|
||
This includes float values and duplicates.
|
||
|
||
**Examples**
|
||
|
||
```python
|
||
>>> # prepare circuit ...
|
||
>>> print(nlocal)
|
||
┌───────┐┌──────────┐┌──────────┐┌──────────┐
|
||
q_0: ┤ Ry(1) ├┤ Ry(θ[1]) ├┤ Ry(θ[1]) ├┤ Ry(θ[3]) ├
|
||
└───────┘└──────────┘└──────────┘└──────────┘
|
||
>>> nlocal.parameters
|
||
{Parameter(θ[1]), Parameter(θ[3])}
|
||
>>> nlocal.ordered_parameters
|
||
[1, Parameter(θ[1]), Parameter(θ[1]), Parameter(θ[3])]
|
||
```
|
||
|
||
**Returns**
|
||
|
||
The parameters objects used in the circuit.
|
||
</Attribute>
|
||
|
||
### parameter\_bounds
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.parameter_bounds">
|
||
Return the parameter bounds.
|
||
|
||
**Returns**
|
||
|
||
The parameter bounds.
|
||
</Attribute>
|
||
|
||
### parameters
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.parameters" />
|
||
|
||
### preferred\_init\_points
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.preferred_init_points">
|
||
The initial points for the parameters. Can be stored as initial guess in optimization.
|
||
|
||
**Returns**
|
||
|
||
The initial values for the parameters, or None, if none have been set.
|
||
</Attribute>
|
||
|
||
### prefix
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.prefix" attributeValue="'circuit'" />
|
||
|
||
### qregs
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.qregs" attributeTypeHint="list[QuantumRegister]">
|
||
A list of the quantum registers associated with the circuit.
|
||
</Attribute>
|
||
|
||
### qubits
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.qubits">
|
||
Returns a list of quantum bits in the order that the registers were added.
|
||
</Attribute>
|
||
|
||
### reps
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.reps">
|
||
The number of times rotation and entanglement block are repeated.
|
||
|
||
**Returns**
|
||
|
||
The number of repetitions.
|
||
</Attribute>
|
||
|
||
### rotation\_blocks
|
||
|
||
<Attribute id="qiskit.circuit.library.EfficientSU2.rotation_blocks">
|
||
The blocks in the rotation layers.
|
||
|
||
**Returns**
|
||
|
||
The blocks in the rotation layers.
|
||
</Attribute>
|
||
</Class>
|
||
|