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

TL;DR

This paper demonstrates that many-body localization induced by a magnetic field gradient in quantum dot arrays can protect quantum coherence from environmental noise, enabling passive error correction for quantum computing.

Contribution

It introduces a method to induce and utilize dynamical $ extit{ extell}$-bits in quantum dot arrays for protecting quantum information against noise.

Findings

Many-body localization is achievable in quantum dot arrays with magnetic field gradients.

Dynamical $ extit{ extell}$-bits are protected from phonons and charge noise.

Thermalization-based logical gates enable passive error correction.

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.