# YGate¶

class YGate(label=None)[source]

The single-qubit Pauli-Y gate ($$\sigma_y$$).

Matrix Representation:

$\begin{split}Y = \begin{pmatrix} 0 & -i \\ i & 0 \end{pmatrix}\end{split}$

Circuit symbol:

┌───┐
q_0: ┤ Y ├
└───┘

Equivalent to a $$\pi$$ radian rotation about the Y axis.

Note

A global phase difference exists between the definitions of $$RY(\pi)$$ and $$Y$$.

$\begin{split}RY(\pi) = \begin{pmatrix} 0 & -1 \\ 1 & 0 \end{pmatrix} = -i Y\end{split}$

The gate is equivalent to a bit and phase flip.

$\begin{split}|0\rangle \rightarrow i|1\rangle \\ |1\rangle \rightarrow -i|0\rangle\end{split}$

Create new Y gate.

Attributes

 YGate.decompositions Get the decompositions of the instruction from the SessionEquivalenceLibrary. YGate.definition Return definition in terms of other basic gates. YGate.label Return gate label YGate.params return instruction params.

Methods

 YGate.add_decomposition(decomposition) Add a decomposition of the instruction to the SessionEquivalenceLibrary. Assemble a QasmQobjInstruction YGate.broadcast_arguments(qargs, cargs) Validation and handling of the arguments and its relationship. YGate.c_if(classical, val) Add classical condition on register classical and value val. YGate.control([num_ctrl_qubits, label, …]) Return a (mutli-)controlled-Y gate. YGate.copy([name]) Copy of the instruction. Return inverted Y gate ($$Y{\dagger} = Y$$) Return True .IFF. DEPRECATED: use instruction.reverse_ops(). YGate.power(exponent) Creates a unitary gate as gate^exponent. Return a default OpenQASM string for the instruction. YGate.repeat(n) Creates an instruction with gate repeated n amount of times. For a composite instruction, reverse the order of sub-instructions. Return a numpy.array for the Y gate.