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High-harmonic generation from an epsilon-near-zero material

Abstract

High-harmonic generation (HHG) is a signature optical phenomenon of strongly driven, nonlinear optical systems. Specifically, the understanding of the HHG process in rare gases has played a key role in the development of attosecond science1. Recently, HHG has also been reported in solids, providing novel opportunities such as controlling strong-field and attosecond processes in dense optical media down to the nanoscale2. Here, we report HHG from a low-loss, indium-doped cadmium oxide thin film by leveraging the epsilon-near-zero (ENZ) effect3,4,5,6,7,8, whereby the real part of the material’s permittivity in certain spectral ranges vanishes, as well as the associated large resonant enhancement of the driving laser field. We find that ENZ-assisted harmonics exhibit a pronounced spectral redshift as well as linewidth broadening, resulting from the photo induced electron heating and the consequent time-dependent ENZ wavelength of the material. Our results provide a new platform to study strong-field and ultrafast electron dynamics in ENZ materials, reveal new degrees of freedom for spectral and temporal control of HHG, and open up the possibilities of compact solid-state attosecond light sources.

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Fig. 1: Sample schematic and linear optical responses.
Fig. 2: HHG from CdO.
Fig. 3: Pump wavelength-dependent HHG.
Fig. 4: HHG spectral shift and broadening.

Data availability

The data that support the plots within this paper and other findings of this study are available from the corresponding authors on reasonable request.

References

  1. 1.

    Krausz, F. & Ivanov, M. Attosecond physics. Rev. Mod. Phys. 81, 163–234 (2009).

    ADS  Article  Google Scholar 

  2. 2.

    Ghimire, S. & Reis, D. A. High-harmonic generation from solids. Nat. Phys. 15, 10–16 (2019).

    Article  Google Scholar 

  3. 3.

    Alam, M. Z., De Leon, I. & Boyd, R. W. Large optical nonlinearity of indium tin oxide in its epsilon-near-zero region. Science 352, 795–797 (2016).

    ADS  Article  Google Scholar 

  4. 4.

    Caspani, L. et al. Enhanced nonlinear refractive index in epsilon-near-zero materials. Phys. Rev. Lett. 116, 233901 (2016).

    ADS  Article  Google Scholar 

  5. 5.

    Engheta, N. Pursuing near-zero response. Science 340, 286–287 (2013).

    ADS  Article  Google Scholar 

  6. 6.

    Luk, T. S. et al. Enhanced third harmonic generation from the epsilon-near-zero modes of ultrathin films. Appl. Phys. Lett. 106, 151103 (2015).

    ADS  Article  Google Scholar 

  7. 7.

    Niu, X., Hu, X., Chu, S. & Gong, Q. Epsilon-near-zero photonics: a new platform for integrated devices. Adv. Opt. Mater. 6, 1701292 (2018).

    Article  Google Scholar 

  8. 8.

    Yang, Y. et al. Femtosecond optical polarization switching using a cadmium oxide-based perfect absorber. Nat. Photon. 11, 390–395 (2017).

    ADS  Article  Google Scholar 

  9. 9.

    McPherson, A. et al. Studies of multiphoton production of vacuum-ultraviolet radiation in the rare gases. J. Opt. Soc. Am. B 4, 595–601 (1987).

    ADS  Article  Google Scholar 

  10. 10.

    Luu, T. T. et al. Extreme ultraviolet high-harmonic spectroscopy of solids. Nature 521, 498–502 (2015).

    ADS  Article  Google Scholar 

  11. 11.

    Ghimire, S. et al. Observation of high-order harmonic generation in a bulk crystal. Nat. Phys. 7, 138–141 (2010).

    Article  Google Scholar 

  12. 12.

    Sivis, M. et al. Tailored semiconductors for high-harmonic optoelectronics. Science 357, 303–306 (2017).

    ADS  Article  Google Scholar 

  13. 13.

    Liu, H. et al. Enhanced high-harmonic generation from an all-dielectric metasurface. Nat. Phys. 14, 1006–1010 (2018).

    Article  Google Scholar 

  14. 14.

    Liu, H. et al. High-harmonic generation from an atomically thin semiconductor. Nat. Phys. 13, 262–265 (2017).

    Article  Google Scholar 

  15. 15.

    Hafez, H. A. et al. Extremely efficient terahertz high-harmonic generation in graphene by hot Dirac fermions. Nature 561, 507–511 (2018).

    ADS  Article  Google Scholar 

  16. 16.

    Garg, M., Kim, H. Y. & Goulielmakis, E. Ultimate waveform reproducibility of extreme-ultraviolet pulses by high-harmonic generation in quartz. Nat. Photon. 12, 291–296 (2018).

    ADS  Article  Google Scholar 

  17. 17.

    Ghimire, S. et al. Generation and propagation of high-order harmonics in crystals. Phys. Rev. A 85, 043836 (2012).

    ADS  Article  Google Scholar 

  18. 18.

    Han, S. et al. High-harmonic generation by field enhanced femtosecond pulses in metal–sapphire nanostructure. Nat. Commun. 7, 13105 (2016).

    ADS  Article  Google Scholar 

  19. 19.

    Vampa, G. et al. Plasmon-enhanced high-harmonic generation from silicon. Nat. Phys. 13, 659–662 (2017).

    Article  Google Scholar 

  20. 20.

    Sachet, E. et al. Dysprosium-doped cadmium oxide as a gateway material for mid-infrared plasmonics. Nat. Mater. 14, 414–420 (2015).

    ADS  Article  Google Scholar 

  21. 21.

    Kelley, K. P., Sachet, E., Shelton, C. T. & Maria, J. P. High mobility yttrium doped cadmium oxide thin films. APL Mater. 5, 076105 (2017).

    ADS  Article  Google Scholar 

  22. 22.

    Naik, G. V., Kim, J. & Boltasseva, A. Oxides and nitrides as alternative plasmonic materials in the optical range. Opt. Mater. Express 1, 1090–1099 (2011).

    ADS  Article  Google Scholar 

  23. 23.

    Stern, E. A. & Ferrell, R. A. Surface plasma oscillations of a degenerate electron gas. Phys. Rev. 120, 130–136 (1960).

    ADS  MathSciNet  Article  Google Scholar 

  24. 24.

    Berreman, D. W. Infrared absorption at longitudinal optic frequency in cubic crystal films. Phys. Rev. 130, 2193–2198 (1963).

    ADS  Article  Google Scholar 

  25. 25.

    Campione, S., Brener, I. & Marquier, F. Theory of epsilon-near-zero modes in ultrathin films. Phys. Rev. B 91, 121408 (2015).

    ADS  Article  Google Scholar 

  26. 26.

    Cimino, A. & Marezio, M. Lattice parameter and defect structure of cadmium oxide containing foreign atoms. J. Phys. Chem. Solids 17, 57–64 (1960).

    ADS  Article  Google Scholar 

  27. 27.

    Guo, P., Schaller, R. D., Ketterson, J. B. & Chang, R. P. H. Ultrafast switching of tunable infrared plasmons in indium tin oxide nanorod arrays with large absolute amplitude. Nat. Photon. 10, 267–273 (2016).

    ADS  Article  Google Scholar 

  28. 28.

    Kane, E. O. Band structure of indium antimonide. J. Phys. Chem. Solids 1, 249–261 (1957).

    ADS  Article  Google Scholar 

  29. 29.

    Turchinovich, D., Hvam, J. M. & Hoffmann, M. C. Self-phase modulation of a single-cycle terahertz pulse by nonlinear free-carrier response in a semiconductor. Phys. Rev. B 85, 201304 (2012).

    ADS  Article  Google Scholar 

  30. 30.

    Wood, M. G. et al. Gigahertz speed operation of epsilon-near-zero silicon photonic modulators. Optica 5, 233–236 (2018).

    ADS  Article  Google Scholar 

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Acknowledgements

This work started when Y.Y. was a postdoctoral researcher at Sandia National Laboratories. The work performed at Sandia National Laboratories was supported by the US Department of Energy (DOE), Office of Basic Energy Sciences, Division of Materials Sciences and Engineering, and performed, in part, at the Center for Integrated Nanotechnologies, an Office of Science User Facility operated for the US DOE Office of Science. Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, a wholly owned subsidiary of Honeywell International, for the US DOE’s National Nuclear Security Administration under contract DE-NA-0003525. The views expressed in this article do not necessarily represent the views of the US DOE or the United States Government. The work performed at SLAC was primarily supported by the US DOE, Office of Science, Basic Energy Sciences, Chemical Sciences, Geosciences and Biosciences Division through the Early Career Research Program. Y.Y. acknowledges support from the Youth Thousand Talent program of China. A.M. acknowledges the National Science Foundation (grant ECCS-1710697) and the UNM Center for Advanced Research Computing for providing high-performance computing resources. J.-P.M. acknowledges support from the National Science Foundation (grant CHE-1507947) and Army Research Office (grants W911NF16-1-0406 and W911NF-16-1-0037). S.G. thanks U. Thumm for stimulating discussions.

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Y.Y. conceived the idea. J.L., Y.Y., T.S.L. and H.L. carried out optical measurements. A.M. developed the theory. K.K., J.-P.M. and E.L.R. prepared the sample. All authors contributed to analysing the data and writing the manuscript. I.B., S.G., M.B.S. and J.-P.M. supervised the project.

Corresponding authors

Correspondence to Yuanmu Yang or Igal Brener.

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The authors declare no competing interests.

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Peer review information: Nature Physics thanks Dmitry Turchinovich and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Yang, Y., Lu, J., Manjavacas, A. et al. High-harmonic generation from an epsilon-near-zero material. Nat. Phys. 15, 1022–1026 (2019). https://doi.org/10.1038/s41567-019-0584-7

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