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workbench_algorithms.subroutines.phase_gradient_unified

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Module containing Qubricks for phase gradient functionality (NaivePhaseGradient, PhaseGradientViaPhaseCatalystState).

NaivePhaseGradient 

NaivePhaseGradient(**kwargs)

Bases: Qubrick

Implement a phase gradient with a specified base angle.

This naive version simply applies a sequence of phase gates with angles that are halved for each subsequent qubit in the target register.

Note
  • For definition of a phase gradient, refer to Craig Gidney's blog post: https://algassert.com/post/1708

compute 

compute(
    target_reg: Qubits,
    base_angle: float | RotationAngle = ...,
    error_param: float = 0,
    ctrl: Qubits | int = 0,
)

Compute phase gradient circuit.

The default base angle is 180 degrees, which corresponds to a Z gate.

Parameters:

Name Type Description Default
target_reg Qubits

Target register upon which to apply rotations (a gradient of rotations).

 required
base_angle float | RotationAngle

Base angle from which subsequent angles are divided by 2^k where k iterates over the target register.

 ...
error_param float

Precision of each angle in phase gradient, not overall error.

 0
ctrl Qubits | int

Quantum control.

 0