Quantum highway: Observation of minimal and maximal speed limits for few and many-body states

• URL: http://arxiv.org/abs/2408.11900v1
• Date: Wed, 21 Aug 2024 18:00:07 GMT
• Title: Quantum highway: Observation of minimal and maximal speed limits for few and many-body states
• Authors: Zitian Zhu, Lei Gao, Zehang Bao, Liang Xiang, Zixuan Song, Shibo Xu, Ke Wang, Jiachen Chen, Feitong Jin, Xuhao Zhu, Yu Gao, Yaozu Wu, Chuanyu Zhang, Ning Wang, Yiren Zou, Ziqi Tan, Aosai Zhang, Zhengyi Cui, Fanhao Shen, Jiarun Zhong, Tingting Li, Jinfeng Deng, Xu Zhang, Hang Dong, Pengfei Zhang, Zhen Wang, Chao Song, Chen Cheng, Qiujiang Guo, Hekang Li, H. Wang, Haiqing Lin, Rubem Mondaini,
• Abstract summary: Inspired by the energy-time uncertainty principle, bounds have been demonstrated on the maximal speed at which a quantum state can change. We show that one can test the known quantum speed limits and that modifying a single Hamiltonian parameter allows the observation of the crossover of the different bounds on the dynamics.
• Score: 19.181412608418608
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Tracking the time evolution of a quantum state allows one to verify the thermalization rate or the propagation speed of correlations in generic quantum systems. Inspired by the energy-time uncertainty principle, bounds have been demonstrated on the maximal speed at which a quantum state can change, resulting in immediate and practical tasks. Based on a programmable superconducting quantum processor, we test the dynamics of various emulated quantum mechanical systems encompassing single- and many-body states. We show that one can test the known quantum speed limits and that modifying a single Hamiltonian parameter allows the observation of the crossover of the different bounds on the dynamics. We also unveil the observation of minimal quantum speed limits in addition to more common maximal ones, i.e., the lowest rate of change of a unitarily evolved quantum state. Our results establish a comprehensive experimental characterization of quantum speed limits and pave the way for their subsequent study in engineered non-unitary conditions.

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