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# iSwapGate

class iSwapGate(label=None)

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iSWAP gate.

A 2-qubit XX+YY interaction. This is a Clifford and symmetric gate. Its action is to swap two qubit states and phase the $|01\rangle$ and $|10\rangle$ amplitudes by i.

Can be applied to a QuantumCircuit with the iswap() method.

Circuit Symbol:

q_0: ─⨂─
│
q_1: ─⨂─

Reference Implementation:

     ┌───┐┌───┐     ┌───┐
q_0: ┤ S ├┤ H ├──■──┤ X ├─────
├───┤└───┘┌─┴─┐└─┬─┘┌───┐
q_1: ┤ S ├─────┤ X ├──■──┤ H ├
└───┘     └───┘     └───┘

Matrix Representation:

$\begin{split}iSWAP = R_{XX+YY}\left(-\frac{\pi}{2}\right) = \exp\left(i \frac{\pi}{4} \left(X{\otimes}X+Y{\otimes}Y\right)\right) = \begin{pmatrix} 1 & 0 & 0 & 0 \\ 0 & 0 & i & 0 \\ 0 & i & 0 & 0 \\ 0 & 0 & 0 & 1 \end{pmatrix}\end{split}$

This gate is equivalent to a SWAP up to a diagonal.

$\begin{split}iSWAP = \begin{pmatrix} 1 & 0 & 0 & 0 \\ 0 & 0 & 1 & 0 \\ 0 & 1 & 0 & 0 \\ 0 & 0 & 0 & 1 \end{pmatrix} . \begin{pmatrix} 1 & 0 & 0 & 0 \\ 0 & i & 0 & 0 \\ 0 & 0 & i & 0 \\ 0 & 0 & 0 & 1 \end{pmatrix}\end{split}$

Create new iSwap gate.

## Methods Defined Here

### power

iSwapGate.power(exponent)

Raise gate to a power.

## Attributes

### condition_bits

Get Clbits in condition.

Return type

List[Clbit]

### decompositions

Get the decompositions of the instruction from the SessionEquivalenceLibrary.

### definition

Return definition in terms of other basic gates.

### duration

Get the duration.

### label

Return instruction label

Return type

str

Return the name.

### num_clbits

Return the number of clbits.

### num_qubits

Return the number of qubits.

### params

return instruction params.

### unit

Get the time unit of duration.