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arXiv · 2204.13354

Protecting coherence from the environment via Stark many-body localization in a Quantum-Dot Simulator

Abstract

Semiconductor platforms are emerging as a promising architecture for storing and processing quantum information, e.g., in quantum dot spin qubits. However, charge noise coming from interactions between the electrons is a major limiting factor, along with the scalability of many qubits, for a quantum computer. We show that a magnetic field gradient can be implemented in a semiconductor quantum dot array to induce a local quantum coherent dynamical $\ell-$bit exhibiting the potential to be used as logical qubits. These dynamical $\ell-$bits are responsible for the model being many-body localized. We show that these dynamical $\ell-$bits and the corresponding many-body localization are protected from all noises, including phonons, for sufficiently long times if electron-phonon interaction is not non-local. We further show the implementation of thermalization-based self-correcting logical gates. This thermalization-based error correction goes beyond the standard paradigm of decoherence-free and noiseless subsystems. Our work thus opens a new venue for passive quantum error correction in semiconductor-based quantum computers.

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Subhajit Sarkar, Berislav Buča. 2024-06-26. Protecting coherence from the environment via Stark many-body localization in a Quantum-Dot Simulator. https://doi.org/10.22331/q-2024-07-02-1392

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