MCPhaseGate#

class qiskit.circuit.library.MCPhaseGate(lam, num_ctrl_qubits, label=None)[source]#

Bases: ControlledGate

Multi-controlled-Phase gate.

This is a diagonal and symmetric gate that induces a phase on the state of the target qubit, depending on the state of the control qubits.

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

Circuit symbol:

    q_0: ───■────
            │
            .
            │
q_(n-1): ───■────
         ┌──┴───┐
    q_n: ┤ P(λ) ├
         └──────┘

See also

CPhaseGate: The singly-controlled-version of this gate.

Create new MCPhase 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.

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.

Methods

control(num_ctrl_qubits=1, label=None, ctrl_state=None)[source]#

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:

ControlledGate

inverse()[source]#: Return inverted MCU1 gate (\(MCU1(\lambda)^{\dagger} = MCU1(-\lambda)\))