Physics-informed Tracking of Qubit Fluctuations

In this latest research from Prof. Ferdinand Kuemmeth’s lab at NBI, a physics-informed and real-time Hamiltonian estimation protocol is applied to a qubit. This protocol estimates the fluctuating environment of a spin qubit (a nuclear spin bath) on-the-fly on the OPX quantum controller, by updating its probability distribution according to the model describing the nuclear spins (Fokker-Planck equation). It is further improved by adaptively choosing the probing time of the qubit based on the previous measurement outcomes, to maximize the information gathered per measurement (arXiv:2404.09212).

The agenda included two parts: 

1. Part I (Fabrizio Berritta, NBI): Overview of the latest research from Ferdinand’s lab at NBI.
2. Part II (Fabio Ansaloni, QM): Quantum dots research with OPX and QDAC use case.