Yuval GEFEN
The challenge of preparing a system in a pre-designated state spans diverse facets of quantum mechanics. To achieve this task of steering towards target quantum states, one can employ quantum control through a sequence of generalized measurements. A standard class of protocols—passive protocols (a.k.a. blind measurements) comprise tracing out the readouts of the detectors. To improve or optimize such protocols one may employ an active version of blind measurements: the obtained measurement readouts are used to adjust the protocol on-the-go, with a possibility for accelerated performance or fidelity increase. We have considered such active measurement-driven steering as applied to the challenging case of many-body quantum systems. The target states of highest interest would be those with multipartite entanglement. Such state preparation in a measurementbased protocol is limited by the natural constraints for system-detector couplings. We have developed a framework for finding such physically feasible couplings, based on parent Hamiltonian construction. For helpful decision-making strategies, we offered two paradigmatic approaches to this challenge, and have deomonstrated that, applying active steering to a set of examples, one may achieve an improvement of the steering speed (as compared with passive steering) by an order of magnitude.