workbench_algorithms.experimental.subroutines.rotations

Subpackage for experimental rotations.

PauliToPauliBasisTransform

PauliToPauliBasisTransform(**kwargs)

Bases: Qubrick

Transforms quantum operations between different Pauli bases (X, Y, Z).

Used to simplify or standardize quantum computations.

y_to_z

y_to_z(qbits: Qubits, ctrl: Qubits | int = 0)

Convert y to z.

x_to_z

x_to_z(qbits: Qubits, ctrl: Qubits | int = 0)

Convert x to z.

pauli_product_to_z

pauli_product_to_z(
    x_qbits: Qubits, z_qbits: Qubits, ctrl: Qubits | int = 0
)

Convert PPO to z.

z_to_y

z_to_y(qbits: Qubits, ctrl: Qubits | int = 0)

Convert z to y.

z_to_x

z_to_x(qbits: Qubits, ctrl: Qubits | int = 0)

Convert z to x.

z_to_pauli_product

z_to_pauli_product(
    x_qbits: Qubits, z_qbits: Qubits, ctrl: Qubits | int = 0
)

Convert z to PPO.

RotationViaPhaseGradientAddition

RotationViaPhaseGradientAddition(
    adder_qbk: Adder | None = None, **kwargs
)

Bases: Qubrick

Coherently-applies WB qc.phase rotations via phase gradient addition.

This method originated from Appendix A in arxiv:2007.07391 (See Appendix D.1.2 in this paper for how this is used to form a multiplexor)

The PGA circuit is defined with respect to phase rotations; as such, implementing any other-axis rotation in a coherent superposition typically requires rotating to the Z basis, in-place adding with a phase gradient, and then rotating back to the original basis.

This Qubrick is a stand-in for that base-case of phase gate.

Parameters:

Name	Type	Description	Default
`adder_qbk`	`Adder \| None`	Qubrick for implementing the addition in the phase gradient addition.	`None`
`kwargs`	`dict[str, Any]`	Other key word arguments to pass to the constructor.	`{}`

compute

compute(
    angle_reg: Qubits,
    target_reg: Qubits,
    rot_data: MultiplexedRotationDataInterface,
    ctrl: Qubits | int = 0,
)

Compute circuit for rotations via phase gradient addition.

Parameters:

Name	Type	Description	Default
`angle_reg`	`Qubits`	Register where rotation angles have been written.	required
`target_reg`	`Qubits`	Single qubit where rotations are applied.	required
`rot_data`	`MultiplexedRotationDataInterface`	discretized rotation angles data for the multiplexor	required
`ctrl`	`Qubits \| int`	Control register.	`0`

RotationViaSingleQubitUnitaries

RotationViaSingleQubitUnitaries(**kwargs)

Bases: Qubrick

Compute circuit for rotations via controlled single-qubit rotations.

See Appendix D.1.1 in this paper for how this is used to form a multiplexor.

Note

Here we note some conventions used in the literature and its correspondence in this Qubrick:

In arXiv:1812.00954, a multiplexed Y rotation is written as \(\text{RY}(\theta_x) = e^{i2\pi \theta_x Y}\), with \(\theta_x\) in radians.
With an explicit factor of \(2\pi\) in the exponent, this implies the angles range from zero to one.
Workbench does not include this factor of \(2\pi\) in its definition of Pauli rotations, so it must be accounted for.
Additionally, the default units in Workbench are degrees, and thus, this is why the angle args below have a factor of 360 in the numerator.
This routine makes use of an integer approximation of \(\theta_x\) by truncating its binary expansion to \(b\) bits.
For these reasons, the integer angle approximations written to a register in this routine take values from zero to \(2^b - 1\).

compute

compute(
    angle_reg: Qubits,
    target_reg: Qubits,
    rot_data: MultiplexedRotationDataInterface,
    ctrl: Qubits | int = 0,
)

Compute circuit for rotations via controlled single qubit rotations.

Parameters:

Name	Type	Description	Default
`angle_reg`	`Qubits`	Register where rotation angles have been written.	required
`target_reg`	`Qubits`	Single qubit where rotations are applied.	required
`rot_data`	`MultiplexedRotationDataInterface`	discretized rotation angles data for the multiplexor	required
`ctrl`	`Qubits \| int`	Control register.	`0`