# new_wamf1_control¶

qctrlopencontrols.new_wamf1_control(rabi_rotation: float, maximum_rabi_rate: float, azimuthal_angle: float = 0.0, name: Optional[str] = None) → qctrlopencontrols.driven_controls.driven_control.DrivenControl[source]

Creates a first-order Walsh amplitude-modulated filter (WAMF1) driven control.

WAMF1 driven controls are robust to low-frequency dephasing noise.

Parameters
• rabi_rotation (float) – The total Rabi rotation $$\theta$$ to be performed by the driven control. Must be either $$\pi/4$$, $$\pi/2$$, or $$\pi$$.

• maximum_rabi_rate (float) – The maximum Rabi frequency $$\Omega_{\rm max}$$ for the driven control.

• azimuthal_angle (float, optional) – The azimuthal angle $$\phi$$ for the rotation. Defaults to 0.

• name (str, optional) – An optional string to name the control. Defaults to None.

Returns

The driven control $$\{(\delta t_n, \Omega_n, \phi_n, \Delta_n)\}$$.

Return type

DrivenControl

Notes

A WAMF1 1 driven control consists of four control segments:

$$\delta t_n$$

$$\Omega_n$$

$$\phi_n$$

$$\Delta_n$$

$$\theta_+/4\Omega_{\rm max}$$

$$\Omega_{\rm max}$$

$$\phi$$

$$0$$

$$\theta_+/4\Omega_{\rm max}$$

$$\Omega_{\rm max}\theta_-/\theta_+$$

$$\phi$$

$$0$$

$$\theta_+/4\Omega_{\rm max}$$

$$\Omega_{\rm max}\theta_-/\theta_+$$

$$\phi$$

$$0$$

$$\theta_+/4\Omega_{\rm max}$$

$$\Omega_{\rm max}$$

$$\phi$$

$$0$$

where $$\theta_\pm = \theta+2\pi k_\theta\pm \delta_\theta$$, and the integer $$k_\theta$$ and offset $$\delta_\theta$$ are optimized numerically in order to maximize the suppression of dephasing noise. Note that the optimal values depend only on the rotation angle $$\theta$$.

This implementation supports $$\theta\in\{\pi/4,\pi/2,\pi\}$$.

References

1

H. Ball and M. J. Biercuk, EPJ Quantum Technology 2, 11 (2015).