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arXiv · 2405.16067

Weaving Complex Graph on simple low-dimensional qubit lattices

Yu-Hang Dang·Shyam Dhamapurkar·Xiao-Long Zhu·Zheng-Yang Zhou·Hao-Yu Guan·Xiu-Hao Deng
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Abstract

In quantum computing, the connectivity of qubits placed on two-dimensional chips limits the scalability and functionality of solid-state quantum computers. This paper presents two approaches to constructing complex quantum networks from simple qubit arrays, specifically grid lattices. The first approach utilizes a subset of qubits as tunable couplers, effectively yielding a range of non-trivial graph-based Hamiltonians. The second approach employs dynamic graph engineering by periodically activating and deactivating couplers, enabling the creation of effective quantum walks with longer-range couplings. Numerical simulations verify the effective dynamics of these approaches. In terms of these two approaches, we explore implementing various graphs, including cubes and fullerenes, etc, on two-dimensional lattices. These techniques facilitate the realization of analog quantum simulation, particularly continuous-time quantum walks discussed in detail in this manuscript, for different computational tasks on superconducting quantum chips despite their inherent low dimensional simple architecture.

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Yu-Hang Dang, Shyam Dhamapurkar, Xiao-Long Zhu, Zheng-Yang Zhou, Hao-Yu Guan, Xiu-Hao Deng. 2024-05-25. Weaving Complex Graph on simple low-dimensional qubit lattices. https://arxiv.org/abs/2405.16067

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