iSwapGate

class iSwapGate(label=None)

Bases: qiskit.circuit.gate.Gate

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

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

name

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.