CZGate#

class qiskit.circuit.library.CZGate(label=None, ctrl_state=None)[Quellcode]#

Bases: ControlledGate

Controlled-Z gate.

This is a Clifford and symmetric gate.

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

Circuit symbol:

q_0: ─■─
      │
q_1: ─■─

Matrix representation:

\[\begin{split}CZ\ q_0, q_1 = I \otimes |0\rangle\langle 0| + Z \otimes |1\rangle\langle 1| = \begin{pmatrix} 1 & 0 & 0 & 0 \\ 0 & 1 & 0 & 0 \\ 0 & 0 & 1 & 0 \\ 0 & 0 & 0 & -1 \end{pmatrix}\end{split}\]

In the computational basis, this gate flips the phase of the target qubit if the control qubit is in the \(|1\rangle\) state.

Create new CZ gate.

Attributes

condition_bits#

Get Clbits in condition.

ctrl_state#

Return the control state of the gate as a decimal integer.

decompositions#

Get the decompositions of the instruction from the SessionEquivalenceLibrary.

definition#

Return definition in terms of other basic gates. If the gate has open controls, as determined from self.ctrl_state, the returned definition is conjugated with X without changing the internal _definition.

duration#

Get the duration.

label#

Return instruction label

name#

Get name of gate. If the gate has open controls the gate name will become:

<original_name_o<ctrl_state>

where <original_name> is the gate name for the default case of closed control qubits and <ctrl_state> is the integer value of the control state for the gate.

num_clbits#

Return the number of clbits.

num_ctrl_qubits#

Get number of control qubits.

Rückgabe:

The number of control qubits for the gate.

Rückgabetyp:

int

num_qubits#

Return the number of qubits.

params#

Get parameters from base_gate.

Rückgabe:

List of gate parameters.

Rückgabetyp:

list

Verursacht:

CircuitError – Controlled gate does not define a base gate

unit#

Get the time unit of duration.

Methods

inverse()[Quellcode]#

Return inverted CZ gate (itself).