Frame-based filter-function formalism for quantum characterization and control - Part II. Noise-tailored gate design*

Abstract: This is the second part of the work ``Frame-based filter-function formalism for quantum characterization and control".

The frame-formalism [https://arxiv.org/abs/2008.13216] leads to a model-reduced representation of the open quantum system dynamics and permitting efficient integration of the control capabilities from the outset, allowing the streamlining of the tasks of characterization and optimal control of open quantum systems.

We demonstrate via numerical simulations an experimentally motivated open multi-qubit system with piecewise noisy control. We show how one can characterize exactly what is needed to execute optimal control given the available control, and demonstrate how very high fidelities can be achieved with only minimal assumptions. We present the model-reduction properties of the formalism by showing only a minimal loss of performance when compared to the (unrealistic) scenario in which full information about the open quantum system is available.