cirq_google.experimental.CouplerPulse

Tunable pulse for entangling adjacent qubits.

cirq_google.experimental.CouplerPulse(
    hold_time: cirq.Duration,
    coupling_mhz: cirq.TParamVal,
    rise_time: Optional[cirq.Duration] = cirq.Duration(nanos=8),
    padding_time: Optional[cirq.Duration] = cirq.Duration(nanos=2.5),
    q0_detune_mhz: cirq.TParamVal = 0.0,
    q1_detune_mhz: cirq.TParamVal = 0.0
)

For experimental usage only.

This operation sends a trapezoidal pulse to the coupler between two adjacent qubits placed in resonance.

Note that this gate does not have a unitary matrix and must be characterized by the user in order to determine its effects.

                 __________
                /          \
_______________/            \________________
 |<---------->|  |<------>|  |<----------->|
  padding_time   hold_time     padding_time
             ->  <-      ->   <-
            rise_time   rise_time

hold_time Length of the 'plateau' part of the coupler trajectory.
coupling_mhz Target qubit-qubit coupling reached at the plateau.
rise_time Width of the rising (or falling) section of the trapezoidal pulse.
padding_time Symmetric padding around the coupler pulse.
q0_detune_mhz Detuning of the first qubit.
q1_detune_mhz Detuning of the second qubit.

Methods

controlled

controlled(
    num_controls: Optional[int] = None,
    control_values: Optional[Union[cv.AbstractControlValues, Sequence[Union[int, Collection[int]]]]
        ] = None,
    control_qid_shape: Optional[Tuple[int, ...]] = None
) -> 'Gate'

Returns a controlled version of this gate. If no arguments are specified, defaults to a single qubit control.

Args
num_controls Total number of control qubits.
control_values Which control computational basis state to apply the sub gate. A sequence of length num_controls where each entry is an integer (or set of integers) corresponding to the computational basis state (or set of possible values) where that control is enabled. When all controls are enabled, the sub gate is applied. If unspecified, control values default to 1.
control_qid_shape The qid shape of the controls. A tuple of the expected dimension of each control qid. Defaults to (2,) * num_controls. Specify this argument when using qudits.

Returns
A cirq.Gate representing self controlled by the given control values and qubits. This is a cirq.ControlledGate in the base implementation, but subclasses may return a different gate type.

num_qubits

View source

num_qubits() -> int

The number of qubits this gate acts on.

on

on(
    *qubits
) -> 'Operation'

Returns an application of this gate to the given qubits.

Args
*qubits The collection of qubits to potentially apply the gate to.

Returns: a cirq.Operation which is this gate applied to the given qubits.

on_each

on_each(
    *targets
) -> List['cirq.Operation']

Returns a list of operations applying the gate to all targets.

Args
*targets The qubits to apply this gate to. For single-qubit gates this can be provided as varargs or a combination of nested iterables. For multi-qubit gates this must be provided as an Iterable[Sequence[Qid]], where each sequence has num_qubits qubits.

Returns
Operations applying this gate to the target qubits.

Raises
ValueError If targets are not instances of Qid or Iterable[Qid]. If the gate qubit number is incompatible.
TypeError If a single target is supplied and it is not iterable.

validate_args

validate_args(
    qubits: Sequence['cirq.Qid']
) -> None

Checks if this gate can be applied to the given qubits.

By default checks that:

  • inputs are of type Qid
  • len(qubits) == num_qubits()
  • qubit_i.dimension == qid_shape[i] for all qubits

Child classes can override. The child implementation should call super().validate_args(qubits) then do custom checks.

Args
qubits The sequence of qubits to potentially apply the gate to.

Raises
ValueError The gate can't be applied to the qubits.

with_probability

with_probability(
    probability: 'cirq.TParamVal'
) -> 'cirq.Gate'

Creates a probabilistic channel with this gate.

Args
probability floating point value between 0 and 1, giving the probability this gate is applied.

Returns
cirq.RandomGateChannel that applies self with probability probability and the identity with probability 1-p.

wrap_in_linear_combination

wrap_in_linear_combination(
    coefficient: Union[complex, float, int] = 1
) -> 'cirq.LinearCombinationOfGates'

Returns a LinearCombinationOfGates with this gate.

Args
coefficient number coefficient to use in the resulting cirq.LinearCombinationOfGates object.

Returns
cirq.LinearCombinationOfGates containing self with a coefficient of coefficient.

__add__

__add__(
    other: Union['Gate', 'cirq.LinearCombinationOfGates']
) -> 'cirq.LinearCombinationOfGates'

__call__

__call__(
    *qubits, **kwargs
)

Call self as a function.

__eq__

__eq__(
    other: _SupportsValueEquality
) -> bool

__mul__

__mul__(
    other: Union[complex, float, int]
) -> 'cirq.LinearCombinationOfGates'

__ne__

__ne__(
    other: _SupportsValueEquality
) -> bool

__neg__

__neg__() -> 'cirq.LinearCombinationOfGates'

__pow__

__pow__(
    power
)

__rmul__

__rmul__(
    other: Union[complex, float, int]
) -> 'cirq.LinearCombinationOfGates'

__sub__

__sub__(
    other: Union['Gate', 'cirq.LinearCombinationOfGates']
) -> 'cirq.LinearCombinationOfGates'

__truediv__

__truediv__(
    other: Union[complex, float, int]
) -> 'cirq.LinearCombinationOfGates'