Theory of active dephasing control in qubit arrays

Masahide Sasaki, Atsushi Hasegawa, Yasuyoshi Mitsumori +1 more

FUJIO MINAMI

Florian Förster, G. Petersen, Stephan Manus +5 more

Jiaqi You, John M. Doyle, Zirui Liu +2 more

We propose and theoretically analyze methods for quantum many-body control through geometric reshaping of molecular tweezer arrays. Dynamic rearrangement during entanglement is readily available due to the extended coherence times of molecular rotational qubits. We show how motional dephasing can be suppressed and enhanced spin squeezing can be achieved in an actively rearranged short-range XY model. We also analyze in detail a specific static geometry that significantly suppresses decoherence. These general methods as applied to programmable quantum systems offer robust control modalities that are well suited to molecules.

Yang Yang, Qing Qing, Ming Ming +2 more

Anna Grodecka, Paweł Machnikowski

We define the collective logical quantum bit as a state on an array of 2, 4, and 8 quantum dots.We show that such an array can be controlled with less phonon-induced pure dephasing than a single dot.We calculate the dephasing accompanying a single-qubit operation on the collective logical qubit by means of perturbative method describing the open system evolution under arbitrary driving.