qiskit-documentation/docs/api/qiskit/0.44/qiskit.circuit.library.RXXG...

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---
title: RXXGate
description: API reference for qiskit.circuit.library.RXXGate
in_page_toc_min_heading_level: 1
python_api_type: class
python_api_name: qiskit.circuit.library.RXXGate
---
# RXXGate
<Class id="qiskit.circuit.library.RXXGate" isDedicatedPage={true} github="https://github.com/qiskit/qiskit/tree/stable/0.25/qiskit/circuit/library/standard_gates/rxx.py" signature="qiskit.circuit.library.RXXGate(theta, label=None)" modifiers="class">
Bases: [`Gate`](qiskit.circuit.Gate "qiskit.circuit.gate.Gate")
A parametric 2-qubit $X \otimes X$ interaction (rotation about XX).
This gate is symmetric, and is maximally entangling at $\theta = \pi/2$.
Can be applied to a [`QuantumCircuit`](qiskit.circuit.QuantumCircuit "qiskit.circuit.QuantumCircuit") with the [`rxx()`](qiskit.circuit.QuantumCircuit#rxx "qiskit.circuit.QuantumCircuit.rxx") method.
**Circuit Symbol:**
```python
┌─────────┐
q_0: ┤1 ├
│ Rxx(ϴ) │
q_1: ┤0 ├
└─────────┘
```
**Matrix Representation:**
$$
\begin{align}\begin{aligned}\newcommand{\th}{\frac{\theta}{2}}\\\begin{split}R_{XX}(\theta) = \exp\left(-i \th X{\otimes}X\right) =
\begin{pmatrix}
\cos\left(\th\right) & 0 & 0 & -i\sin\left(\th\right) \\
0 & \cos\left(\th\right) & -i\sin\left(\th\right) & 0 \\
0 & -i\sin\left(\th\right) & \cos\left(\th\right) & 0 \\
-i\sin\left(\th\right) & 0 & 0 & \cos\left(\th\right)
\end{pmatrix}\end{split}\end{aligned}\end{align}
$$
**Examples:**
> $$
> R_{XX}(\theta = 0) = I
> $$
>
> $$
> R_{XX}(\theta = \pi) = i X \otimes X
> $$
>
> $$
> \begin{split}R_{XX}\left(\theta = \frac{\pi}{2}\right) = \frac{1}{\sqrt{2}}
> \begin{pmatrix}
> 1 & 0 & 0 & -i \\
> 0 & 1 & -i & 0 \\
> 0 & -i & 1 & 0 \\
> -i & 0 & 0 & 1
> \end{pmatrix}\end{split}
> $$
Create new RXX gate.
## Attributes
### condition\_bits
<Attribute id="qiskit.circuit.library.RXXGate.condition_bits">
Get Clbits in condition.
</Attribute>
### decompositions
<Attribute id="qiskit.circuit.library.RXXGate.decompositions">
Get the decompositions of the instruction from the SessionEquivalenceLibrary.
</Attribute>
### definition
<Attribute id="qiskit.circuit.library.RXXGate.definition">
Return definition in terms of other basic gates.
</Attribute>
### duration
<Attribute id="qiskit.circuit.library.RXXGate.duration">
Get the duration.
</Attribute>
### label
<Attribute id="qiskit.circuit.library.RXXGate.label">
Return instruction label
</Attribute>
### name
<Attribute id="qiskit.circuit.library.RXXGate.name">
Return the name.
</Attribute>
### num\_clbits
<Attribute id="qiskit.circuit.library.RXXGate.num_clbits">
Return the number of clbits.
</Attribute>
### num\_qubits
<Attribute id="qiskit.circuit.library.RXXGate.num_qubits">
Return the number of qubits.
</Attribute>
### params
<Attribute id="qiskit.circuit.library.RXXGate.params">
return instruction params.
</Attribute>
### unit
<Attribute id="qiskit.circuit.library.RXXGate.unit">
Get the time unit of duration.
</Attribute>
## Methods
### inverse
<Function id="qiskit.circuit.library.RXXGate.inverse" signature="inverse()">
Return inverse RXX gate (i.e. with the negative rotation angle).
</Function>
### power
<Function id="qiskit.circuit.library.RXXGate.power" signature="power(exponent)">
Raise gate to a power.
</Function>
</Class>