aiqbench analysis
This research proposes a novel method for mobile spin qubits to "leapfrog" over stationary electrons in silicon processors by utilizing the valley degree of freedom in low valley splitting regions. The approach not only enhances routing flexibility but also enables entangling SWAP$^\gamma$ two-qubit gate operations, offering a solution to connectivity challenges in specific chip architectures. By turning previously problematic areas into functional components, this work advances the scalability and operational robustness of semiconductor spin-qubit devices.
Spin Qubit Leapfrogging: Dynamics of shuttling electrons on top of another
arXiv:2604.13760v2 Announce Type: replace-cross Abstract: Spin shuttling has crystalized as a powerful and promising tool for establishing intermediate-range connectivity in semiconductor spin-qubit devices. Although experimental demonstrations have performed exceptionally well on different materials platforms, the question of how to handle areas of low valley splitting in silicon during shuttling remains unresolved. In this work, we explore the possibility of utilizing the valley degree of freedom, particularly in regions of low valley splitting, to allow mobile spin qubits to be shuttled through an occupied stationary quantum dot, thereby leapfrogging over the stationary electron. This not only grants a more enriched mobility for shuttled electrons, as it opens new possible routing paths, but also enables the implementation of an entangling SWAP$^\gamma$ two-qubit gate operation in the process. Simulating this process for different sets of parameters, we demonstrate the feasibility of such an operation and offer a unique use case for otherwise precarious regions of a quantum processor chip and propose a possible extension to the set of possible operations for silicon spin qubit devices.
Abstract:Spin shuttling has crystalized as a powerful and promising tool for establishing intermediate-range connectivity in semiconductor spin-qubit devices. Although experimental demonstrations have performed exceptionally well on different materials platforms, the question of how to handle areas of low valley splitting in silicon during shuttling remains unresolved. In this work, we explore the possibility of utilizing the valley degree of freedom, particularly in regions of low valley splitting, to allow mobile spin qubits to be shuttled through an occupied stationary quantum dot, thereby leapfrogging over the stationary electron. This not only grants a more enriched mobility for shuttled electrons, as it opens new possible routing paths, but also enables the implementation of an entangling SWAP$^\gamma$ two-qubit gate operation in the process. Simulating this process for different sets of parameters, we demonstrate the feasibility of such an operation and offer a unique use case for otherwise precarious regions of a quantum processor chip and propose a possible extension to the set of possible operations for silicon spin qubit devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall); Quantum Physics (quant-ph)
arXiv:2604.13760 [cond-mat.mes-hall]
(or arXiv:2604.13760v2 [cond-mat.mes-hall] for this version)
https://doi.org/10.48550/arXiv.2604.13760 Focus to learn more arXiv-issued DOI via DataCite
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