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Robust reconfigurable electromagnetic pathways within a photonic topological insulator

Nature Materials volume 15, pages 542–548 (2016)Cite this article

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Abstract

The discovery of topological photonic states has revolutionized our understanding of electromagnetic propagation and scattering. Endowed with topological robustness, photonic edge modes are not reflected from structural imperfections and disordered regions. Here we demonstrate robust propagation along reconfigurable pathways defined by synthetic gauge fields within a topological photonic metacrystal. The flow of microwave radiation in helical edge modes following arbitrary contours of the synthetic gauge field between bianisotropic metacrystal domains is unimpeded. This is demonstrated in measurements of the spectrum of transmission and time delay along the topological domain walls. These results provide a framework for freely steering electromagnetic radiation within photonic structures.

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Figure 1: Reconfigurable metacrystal and its bulk band structure.
Figure 2: Topological interfaces in the metacrystal and their edge band diagrams.
Figure 3: Experimental verification of reconfigurable guiding and exponential confinement of the topological edge modes.
Figure 4: Experimental demonstration of spin-locked wave-division of an edge mode at a four-port topological junction.
Figure 5: Experimental demonstration of ballistic transport of the topological edge modes through randomly shaped domain walls and disordered regions.
Figure 6: Demonstration of reconfigurable topological switch and its time-resolved dynamics.

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References

  1. Bernevig, B. A., Hughes, T. L. & Zhang, S. C. Quantum spin Hall effect and topological phase transition in HgTe quantum wells. Science 314, 1757–1761 (2006).

    Article  CAS  Google Scholar 

  2. Hasan, M. Z. & Kane, C. L. Colloquium: topological insulators. Rev. Mod. Phys. 82, 3045–3067 (2010).

    Article  CAS  Google Scholar 

  3. Kane, C. L. & Mele, E. J. Z2 topological order and the quantum spin Hall effect. Phys. Rev. Lett. 95, 146802 (2005).

    Article  CAS  Google Scholar 

  4. Kane, C. L. & Mele, E. J. Quantum spin Hall effect in graphene. Phys. Rev. Lett. 95, 226801 (2005).

    Article  CAS  Google Scholar 

  5. Qi, X.-L. & Zhang, S.-C. Topological insulators and superconductors. Rev. Mod. Phys. 83, 1057–1110 (2011).

    Article  CAS  Google Scholar 

  6. Fu, L. Topological crystalline insulators. Phys. Rev. Lett. 106, 106802 (2011).

    Article  Google Scholar 

  7. Dziawa, P. et al. Topological crystalline insulator states in Pb1−xSnxSe. Nature Mater. 11, 1023–1027 (2012).

    Article  CAS  Google Scholar 

  8. Prodan, E. & Prodan, C. Topological phonon modes and their role in dynamic instability of microtubules. Phys. Rev. Lett. 103, 248101 (2009).

    Article  Google Scholar 

  9. Kane, C. L. & Lubensky, T. C. Topological boundary modes in isostatic lattices. Nature Phys. 10, 39–45 (2014).

    Article  CAS  Google Scholar 

  10. Yang, Z. et al. Topological acoustics. Phys. Rev. Lett. 114, 114301 (2015).

    Article  Google Scholar 

  11. Khanikaev, A. B., Fleury, R., Mousavi, S. H. & Alù, A. Topologically robust sound propagation in an angular-momentum-biased graphene-like resonator lattice. Nature Commun. 6, 8260 (2015).

    Article  CAS  Google Scholar 

  12. Mousavi, S. H., Khanikaev, A. B. & Wang, Z. Topologically protected elastic waves in phononic metamaterials. Nature Commun. 6, 8682 (2015).

    Article  Google Scholar 

  13. Bliokh, K. Y., Smirnova, D. & Nori, F. Quantum spin Hall effect of light. Science 348, 1448–1451 (2015).

    Article  CAS  Google Scholar 

  14. Lu, L., Joannopoulos, J. D. & Soljaćić, M. Topological photonics. Nature Photon. 8, 821–829 (2014).

    Article  CAS  Google Scholar 

  15. Haldane, F. & Raghu, S. Possible realization of directional optical waveguides in photonic crystals with broken time-reversal symmetry. Phys. Rev. Lett. 100, 013904 (2008).

    Article  CAS  Google Scholar 

  16. Raghu, S. & Haldane, F. D. M. Analogs of quantum-Hall-effect edge states in photonic crystals. Phys. Rev. A 78, 033834 (2008).

    Article  Google Scholar 

  17. Wang, Z., Chong, Y., Joannopoulos, J. & Soljačić, M. Reflection-free one-way edge modes in a gyromagnetic photonic crystal. Phys. Rev. Lett. 100, 13905 (2008).

    Article  Google Scholar 

  18. Wang, Z., Chong, Y., Joannopoulos, J. D. & Soljačić, M. Observation of unidirectional backscattering-immune topological electromagnetic states. Nature 461, 772–775 (2009).

    Article  CAS  Google Scholar 

  19. Poo, Y., Wu, R., Lin, Z., Yang, Y. & Chan, C. T. Experimental realization of self-guiding unidirectional electromagnetic edge states. Phys. Rev. Lett. 106, 093903 (2011).

    Article  Google Scholar 

  20. Fang, K., Yu, Z. & Fan, S. Microscopic theory of photonic one-way edge mode. Phys. Rev. B 84, 075477 (2011).

    Article  Google Scholar 

  21. Fang, K., Yu, Z. & Fan, S. Realizing effective magnetic field for photons by controlling the phase of dynamic modulation. Nature Photon. 6, 782–787 (2012).

    Article  CAS  Google Scholar 

  22. Umucalılar, R. O. & Carusotto, I. Artificial gauge field for photons in coupled cavity arrays. Phys. Rev. A 84, 043804 (2011).

    Article  Google Scholar 

  23. Hafezi, M., Demler, E. A., Lukin, M. D. & Taylor, J. M. Robust optical delay lines with topological protection. Nature Phys. 7, 907–912 (2011).

    Article  CAS  Google Scholar 

  24. Hafezi, M., Mittal, S., Fan, J., Migdall, A. & Taylor, J. M. Imaging topological edge states in silicon photonics. Nature Photon. 7, 1001–1005 (2013).

    Article  CAS  Google Scholar 

  25. Khanikaev, A. B. et al. Photonic topological insulators. Nature Mater. 12, 233–239 (2013).

    Article  CAS  Google Scholar 

  26. Rechtsman, M. C. et al. Photonic Floquet topological insulators. Nature 496, 196–200 (2013).

    Article  CAS  Google Scholar 

  27. Lu, L., Fu, L., Joannopoulos, J. D. & Soljačić, M. Weyl points and line nodes in gyroid photonic crystals. Nature Photon. 7, 294–299 (2013).

    Article  CAS  Google Scholar 

  28. Chen, W.-J. et al. Experimental realization of photonic topological insulator in a uniaxial metacrystal waveguide. Nature Commun. 5, 6782 (2014).

    Google Scholar 

  29. Sounas, D. L., Caloz, C. & Alù, A. Giant non-reciprocity at the subwavelength scale using angular momentum-biased metamaterials. Nature Commun. 4, 2407 (2014).

    Article  Google Scholar 

  30. Tzuang, L. D., Fang, K., Nussenzveig, P., Fan, S. & Lipson, M. Non-reciprocal phase shift induced by an effective magnetic flux for light. Nature Photon. 8, 701–705 (2014).

    Article  CAS  Google Scholar 

  31. Estep, N. A., Sounas, D. L., Soric, J. & Alù, A. Magnetic-free non-reciprocity and isolation based on parametrically modulated coupled-resonator loops. Nature Phys. 10, 923–927 (2014).

    Article  CAS  Google Scholar 

  32. Fang, K. & Fan, S. Controlling the flow of light using the inhomogeneous effective gauge field that emerges from dynamic modulation. Phys. Rev. Lett. 111, 203901 (2013).

    Article  Google Scholar 

  33. Mittal, S. et al. Topologically robust transport of photons in a synthetic gauge field. Phys. Rev. Lett. 113, 087403 (2014).

    Article  CAS  Google Scholar 

  34. Liu, J. et al. Spin-filtered edge states with an electrically tunable gap in a two-dimensional topological crystalline insulator. Nature Mater. 13, 178–183 (2014).

    Article  CAS  Google Scholar 

  35. Aivazian, G. et al. Magnetic control of valley pseudospin in monolayer WSe2 . Nature Phys. 11, 148–152 (2015).

    Article  CAS  Google Scholar 

  36. Srivastava, A. et al. Valley Zeeman effect in elementary optical excitations of monolayer WSe2 . Nature Phys. 11, 141–147 (2015).

    Article  CAS  Google Scholar 

  37. Kwon, D.-H., Wang, X., Bayraktar, Z., Weiner, B. & Werner, D. H. Near-infrared metamaterial films with reconfigurable transmissive/reflective properties. Opt. Lett. 33, 545–547 (2008).

    Article  CAS  Google Scholar 

  38. Ou, J. Y., Plum, E., Jiang, L. & Zheludev, N. I. Reconfigurable photonic metamaterials. Nano Lett. 11, 2142–2144 (2011).

    Article  CAS  Google Scholar 

  39. Ou, J.-Y., Plum, E., Zhang, J. & Zheludev, N. I. An electromechanically reconfigurable plasmonic metamaterial operating in the near-infrared. Nature Nanotech. 8, 252–255 (2013).

    Article  CAS  Google Scholar 

  40. Markos, O. & Soukoulis, C. M. Wave Propagation: from Electrons to Photonic Crystals and Left-Handed Materials (Princeton Univ. Press, 2008).

    Book  Google Scholar 

  41. Cai, W. & Shalaev, V. Optical Metamaterials: Fundamentals and Applications (Springer, 2009).

    Google Scholar 

  42. Serdyukov, A. N., Semchenko, I. V., Tretyakov, S. A. & Sihvola, A. Electromagnetics of Bi-Anisotropic Materials: Theory and Applications (Gordon and Breach Science, 2001).

    Google Scholar 

  43. Ma, T., Khanikaev, A. B., Mousavi, S. H. & Shvets, G. Guiding electromagnetic waves around sharp corners: topologically protected photonic transport in metawaveguides. Phys. Rev. Lett. 114, 127401 (2015).

    Article  Google Scholar 

  44. Halperin, B. I. Quantized Hall conductance, current-carrying edge states, and the existence of extended states in a two-dimensional disordered potential. Phys. Rev. B 25, 2185–2190 (1982).

    Article  Google Scholar 

  45. Khanikaev, A. B. & Genack, A. Viewpoint: light avoids Anderson localization. Physics 7, 87 (2014).

    Article  Google Scholar 

  46. Schwartz, T., Bartal, G., Fishman, S. & Segev, M. Transport and Anderson localization in disordered two-dimensional photonic lattices. Nature 446, 52–55 (2007).

    Article  CAS  Google Scholar 

  47. Avishai, Y. & Band, Y. B. One-dimensional density of states and the phase of the transmission amplitude. Phys. Rev. B 32, 2674–2676 (1985).

    Article  CAS  Google Scholar 

  48. Iannacone, G. General relation between density of states and dwell times in mesoscopic systems. Phys. Rev. B 51, 4727–4729 (1995).

    Article  Google Scholar 

  49. Genack, A. Z., Sebbah, P., Stoytchev, M. & van Tiggelen, B. A. Statistics of wave dynamics in random media. Phys. Rev. Lett. 82, 715 (1999).

    Article  CAS  Google Scholar 

  50. Davy, M., Shi, Z., Wang, J., Cheng, X. & Genack, A. Z. Transmission eigenchannels and the densities of states of random media. Phys. Rev. Lett. 114, 033901 (2015).

    Article  Google Scholar 

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Acknowledgements

The implementation of the metacrystal structure benefited greatly from discussions and machining of H. Rose. X. Ma helped carry out the measurements and H. Zheng assisted in the fabrication of the structure. This research was supported by the National Science Foundation (CMMI-1537294 and DMR-1207446).

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Author notes

  1. Xiaojun Cheng and Camille Jouvaud: These authors contributed equally to this work.

Authors and Affiliations

  1. Department of Physics, Queens College of the City University of New York, Queens, New York 11367, USA

    Xiaojun Cheng, Camille Jouvaud, Xiang Ni, Azriel Z. Genack & Alexander B. Khanikaev

  2. The Graduate Center of the City University of New York, New York, New York 10016, USA

    Xiaojun Cheng, Xiang Ni, Azriel Z. Genack & Alexander B. Khanikaev

  3. Microelectronics Research Center, Cockrell School of Engineering, University of Texas at Austin, Austin, Texas 78758, USA

    S. Hossein Mousavi

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  1. Xiaojun Cheng
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All authors contributed extensively to the work presented in this paper.

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Correspondence to Azriel Z. Genack or Alexander B. Khanikaev.

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Cheng, X., Jouvaud, C., Ni, X. et al. Robust reconfigurable electromagnetic pathways within a photonic topological insulator. Nature Mater 15, 542–548 (2016). https://doi.org/10.1038/nmat4573

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