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arXiv · 2501.06743

Synthetic $π$-flux system in 2D superconducting qubit array with tunable coupling

Yiting Liu·Jiawei Zhang·Zechen Guo·Peisheng Huang·Wenhui Huang·Yongqi Liang·Jiawei Qiu·Xuandong Sun·Zilin Wang·Changrong Xie·Xiaohan Yang·Jiajian Zhang·Libo Zhang·Ji Chu·Weijie Guo·Ji Jiang·Xiayu Linpeng·Song Liu·Jingjing Niu·Yuxuan Zhou·Youpeng Zhong·Wenhui Ren·Ziyu Tao·Dapeng Yu
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Abstract

Flat-band systems provide an ideal platform for exploring exotic quantum phenomena, where the strongly suppressed kinetic energy in these flat energy bands suggests the potential for exotic phases driven by geometric structure, disorder, and interactions. While intriguing phenomena and physical mechanisms have been unveiled in theoretical models, synthesizing such systems within scalable quantum platforms remains challenging. Here, we present the experimental realization of a $π$-flux rhombic system using a two-dimensional superconducting qubit array with tunable coupling. We experimentally observe characteristic dynamics, e.g., $π$-flux driven destructive interference, and demonstrate the protocol for eigenstate preparation in this rhombic array with coupler-assisted flux. Our results provide future possibilities for exploring the interplay of geometry, interactions, and quantum information encoding in such degenerate systems.

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Yiting Liu, Jiawei Zhang, Zechen Guo, Peisheng Huang, Wenhui Huang, Yongqi Liang, Jiawei Qiu, Xuandong Sun, Zilin Wang, Changrong Xie, Xiaohan Yang, Jiajian Zhang, Libo Zhang, Ji Chu, Weijie Guo, Ji Jiang, Xiayu Linpeng, Song Liu, Jingjing Niu, Yuxuan Zhou, Youpeng Zhong, Wenhui Ren, Ziyu Tao, Dapeng Yu. 2025-06-15. Synthetic $π$-flux system in 2D superconducting qubit array with tunable coupling. https://doi.org/10.1063/5.0268772

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