CPhaseGate
class CPhaseGate(theta, label=None, ctrl_state=None)
Bases: qiskit.circuit.controlledgate.ControlledGate
Controlled-Phase gate.
This is a diagonal and symmetric gate that induces a phase on the state of the target qubit, depending on the control state.
Can be applied to a QuantumCircuit with the cp() method.
Circuit symbol:
q_0: ─■──
│λ
q_1: ─■──Matrix representation:
CRZGate: Due to the global phase difference in the matrix definitions of Phase and RZ, CPhase and CRZ are different gates with a relative phase difference.
Create new CPhase gate.
Methods Defined Here
control
CPhaseGate.control(num_ctrl_qubits=1, label=None, ctrl_state=None)
Controlled version of this gate.
Parameters
- num_ctrl_qubits (int) – number of control qubits.
- label (str or None) – An optional label for the gate [Default: None]
- ctrl_state (int or str or None) – control state expressed as integer, string (e.g. ‘110’), or None. If None, use all 1s.
Returns
controlled version of this gate.
Return type
inverse
CPhaseGate.inverse()
Return inverted CPhase gate ()
Attributes
condition_bits
ctrl_state
Return the control state of the gate as a decimal integer.
Return type
int
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.
Return type
List
duration
Get the duration.
label
Return instruction label
Return type
str
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.
Return type
str
num_clbits
Return the number of clbits.
num_ctrl_qubits
Get number of control qubits.
Returns
The number of control qubits for the gate.
Return type
int
num_qubits
Return the number of qubits.
params
Get parameters from base_gate.
Returns
List of gate parameters.
Return type
list
Raises
CircuitError – Controlled gate does not define a base gate
unit
Get the time unit of duration.