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Many-body Hilbert space scarring on a superconducting processor


Quantum many-body scarring (QMBS) is a recently discovered form of weak ergodicity breaking in strongly interacting quantum systems, which presents opportunities for mitigating thermalization-induced decoherence in quantum information processing applications. However, the existing experimental realizations of QMBS are based on systems with specific kinetic constrains. Here we experimentally realize a distinct kind of QMBS by approximately decoupling a part of the many-body Hilbert space in the computational basis. Utilizing a programmable superconducting processor with 30 qubits and tunable couplings, we realize Hilbert space scarring in a non-constrained model in different geometries, including a linear chain and quasi-one-dimensional comb geometry. By reconstructing the full quantum state through quantum state tomography on four-qubit subsystems, we provide strong evidence for QMBS states by measuring qubit population dynamics, quantum fidelity and entanglement entropy after a quench from initial unentangled states. Our experimental findings broaden the realm of scarring mechanisms and identify correlations in QMBS states for quantum technology applications.

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Fig. 1: Experimental setup and identification of QMBS states via quantum state tomography.
Fig. 2: Experimentally observed qubit dynamics.
Fig. 3: Scaling behaviour.
Fig. 4: QMBS states in a comb tensor system.

Data availability

The data that support the findings of this study are available at

Code availability

All the relevant source codes are available from the corresponding authors upon reasonable request.


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The device was fabricated at the Micro-Nano Fabrication Center of Zhejiang University. We acknowledge support from the National Natural Science Foundation of China (grant nos. 92065204, U20A2076, 11725419 and 12174342), the National Basic Research Program of China (grant no. 2017YFA0304300) and the Zhejiang Province Key Research and Development Program (grant no. 2020C01019). The work at Arizona State University is supported by AFOSR through grant no. FA9550-21-1-0186. Z.P. and J.Y.D. acknowledge support by EPSRC grants EP/R020612/1 and EP/R513258/1, and by Leverhulme Trust Research Leadership Award RL-2019-015. L.Y. is also supported by the Fundamental Research Funds for the Central Universities.

Author information

Authors and Affiliations



L.Y. proposed the idea. L.Y., Y.-C.L., J.Y.D. and Z.P. developed the theory and numerical simulation. P.Z., H.D. and Y.G. performed the experiment, and H.L. and J.C. fabricated the device supervised by H.W. L.Z. and J.H. developed the measurement electronics. L.Y., H.W., Y.-C.L. and Z.P. co-wrote the manuscript. All the authors contributed to the experimental setup, discussions of the results and development of the manuscript.

Corresponding authors

Correspondence to Lei Ying, H. Wang or Ying-Cheng Lai.

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Extended data

Extended Data Fig. 1 Experimental sequence diagram.

Sequence with strongly interacting many-body dynamics, where injecting a π pulse (red wave pulse) serves to lift the two-level qubit from the ground state to the excited state.

Supplementary information

Supplementary Information

Supplementary Figs. 1–20, Tables 1 and 2 and discussion.

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Zhang, P., Dong, H., Gao, Y. et al. Many-body Hilbert space scarring on a superconducting processor. Nat. Phys. 19, 120–125 (2023).

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