Abstract

Strategic manipulation of wave and particle transport in various media is the key driving force for modern information processing and communication. In a strongly scattering medium, waves and particles exhibit versatile transport characteristics such as localization1,2, tunnelling with exponential decay3, ballistic4, and diffusion behaviours5 due to dynamical multiple scattering from strong scatters or impurities. Recent investigations of graphene6 have offered a unique approach, from a quantum point of view, to design the dispersion of electrons on demand, enabling relativistic massless Dirac quasiparticles, and thus inducing low-loss transport either ballistically or diffusively. Here, we report an experimental demonstration of an artificial phononic graphene tailored for surface phonons on a LiNbO3 integrated platform. The system exhibits Dirac quasiparticle-like transport, that is, pseudo-diffusion at the Dirac point, which gives rise to a thickness-independent temporal beating for transmitted pulses, an analogue of Zitterbewegung effects7,8,9. The demonstrated fully integrated artificial phononic graphene platform here constitutes a step towards on-chip quantum simulators of graphene and unique monolithic electro-acoustic integrated circuits.

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Acknowledgements

We thank Z. Shi and X. Zhang for helpful discussions. This work was jointly supported by the National Basic Research Program of China (Grant No. 2012CB921503, No. 2013CB632904 and No. 2013CB632702), the National Nature Science Foundation of China (Grant No. 11134006, No. 11474158, and No. 11404164), and the Natural Science Foundation of Jiangsu Province (BK20140019). We also acknowledge the project funded by the Priority Academic Program Development of Jiangsu Higher Education (PAPD) and China Postdoctoral Science Foundation (Grant No. 2012M511249 and No. 2013T60521). L.F. acknowledges support from the National Science Foundation (DMR-1506884 and ECCS-1507312).

Author information

Author notes

    • Si-Yuan Yu
    •  & Xiao-Chen Sun

    These authors contributed equally to this work.

Affiliations

  1. National Laboratory of Solid-State Microstructures and Department of Materials Science and Engineering, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, China

    • Si-Yuan Yu
    • , Xiao-Chen Sun
    • , Xu Ni
    • , Qing Wang
    • , Xue-Jun Yan
    • , Cheng He
    • , Xiao-Ping Liu
    • , Ming-Hui Lu
    •  & Yan-Feng Chen
  2. Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China

    • Xiao-Ping Liu
    • , Ming-Hui Lu
    •  & Yan-Feng Chen
  3. Department of Electrical Engineering, The State University of New York at Buffalo, Buffalo, New York 14260, USA

    • Liang Feng

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Contributions

M.-H.L. and X.-P.L. conceived the idea. M.-H.L., X.-P.L. and Y.-F.C. coordinated and guided the project. S.-Y.Y. designed the devices, fabricated the samples and carried out the measurements. X.-C.S. performed the theoretical analysis. All the authors contributed to discussion of the project. S.-Y.Y., X.-P.L., L.F. and M.-H.L. prepared the manuscript with revisions from other authors.

Competing interests

The authors declare no competing financial interests.

Corresponding authors

Correspondence to Xiao-Ping Liu or Ming-Hui Lu or Yan-Feng Chen.

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DOI

https://doi.org/10.1038/nmat4743

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