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arXiv · 2210.10553

Qubit-environment entanglement outside of pure decoherence: hyperfine interaction

Tymoteusz Salamon·Marcin Płodzień·Maciej Lewenstein·Katarzyna Roszak
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Abstract

In spin-based architectures of quantum devices, the hyperfine interaction between the electron spin qubit and the nuclear spin environment remains one of the main sources of decoherence. This paper provides a short review of the current advances in the theoretical description of the qubit decoherence dynamics. Next, we study the qubit-environment entanglement using negativity as its measure. For an initial maximally mixed state of the environment, we study negativity dynamics as a function of environment size, changing the numbers of environmental nuclei and the total spin of the nuclei. Furthermore, we study the effect of the magnetic field on qubit-environment disentangling time scales.

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Tymoteusz Salamon, Marcin Płodzień, Maciej Lewenstein, Katarzyna Roszak. 2022-10-19. Qubit-environment entanglement outside of pure decoherence: hyperfine interaction. https://doi.org/10.1103/physrevb.107.085428

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