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Ultrafast switching of tunable infrared plasmons in indium tin oxide nanorod arrays with large absolute amplitude


All-optical control of plasmons can enable optical switches with high speeds, small footprints and high on/off ratios. Here we demonstrate ultrafast plasmon modulation in the near-infrared (NIR) to mid-infrared (MIR) range by intraband pumping of indium tin oxide nanorod arrays (ITO-NRAs). We observe redshifts of localized surface plasmon resonances arising from a change of the plasma frequency of ITO, which is governed by the conduction band non-parabolicity. We generalize the plasma frequency for non-parabolic bands, quantitatively model the fluence-dependent plasma frequency shifts, and show that different from noble metals, the lower electron density in ITO enables a remarkable change of electron distributions, yielding a significant plasma frequency modulation and concomitant large transient bleaches and induced absorptions, which can be tuned spectrally by tailoring the ITO-NRA geometry. The low electron heat capacity explains the sub-picosecond kinetics that is much faster than noble metals. Our work demonstrates a new scheme to control infrared plasmons for optical switching, telecommunications and sensing.

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Figure 1: Static optical characterization and simulation of plasmonic ITO-NRA in the infrared.
Figure 2: Transient absorption measurements of the ITO-NRA in both the NIR and MIR.
Figure 3: Non-parabolic band-induced plasma frequency modulation.
Figure 4: Tunability of the MIR transient response through changing incidence angles and ITO-NRA geometries.


  1. 1

    Anker, J. N. et al. Biosensing with plasmonic nanosensors. Nature Mater. 7, 442–453 (2008).

    ADS  Article  Google Scholar 

  2. 2

    Sidiropoulos, T. P. H. et al. Ultrafast plasmonic nanowire lasers near the surface plasmon frequency. Nature Phys. 10, 870–876 (2014).

    ADS  Article  Google Scholar 

  3. 3

    Oulton, R. F. et al. Plasmon lasers at deep subwavelength scale. Nature 461, 629–632 (2009).

    ADS  Article  Google Scholar 

  4. 4

    Atwater, H. A. & Polman, A. Plasmonics for improved photovoltaic devices. Nature Mater. 9, 205–213 (2010).

    ADS  Article  Google Scholar 

  5. 5

    Yu, N. & Capasso, F. Flat optics with designer metasurfaces. Nature Mater. 13, 139–150 (2014).

    ADS  Article  Google Scholar 

  6. 6

    Aouani, H., Rahmani, M., Navarro-Cia, M. & Maier, S. A. Third-harmonic-upconversion enhancement from a single semiconductor nanoparticle coupled to a plasmonic antenna. Nature Nanotech. 9, 290–294 (2014).

    ADS  Article  Google Scholar 

  7. 7

    Kauranen, M. & Zayats, A. V. Nonlinear plasmonics. Nature Photon. 6, 737–748 (2012).

    ADS  Article  Google Scholar 

  8. 8

    Li, W. et al. Ultrafast all-optical graphene modulator. Nano Lett. 14, 955–959 (2014).

    ADS  Article  Google Scholar 

  9. 9

    MacDonald, K. F., Samson, Z. L., Stockman, M. I. & Zheludev, N. I. Ultrafast active plasmonics. Nature Photon. 3, 55–58 (2009).

    ADS  Article  Google Scholar 

  10. 10

    Wurtz, G. A. et al. Designed ultrafast optical nonlinearity in a plasmonic nanorod metamaterial enhanced by nonlocality. Nature Nanotech. 6, 107–111 (2011).

    ADS  Article  Google Scholar 

  11. 11

    Harutyunyan, H. et al. Anomalous ultrafast dynamics of hot plasmonic electrons in nanostructures with hot spots. Nature Nanotech. 10, 770–774 (2015).

    ADS  Article  Google Scholar 

  12. 12

    Noginov, M. A. et al. Transparent conductive oxides: Plasmonic materials for telecom wavelengths. Appl. Phys. Lett. 99, 021101 (2011).

    ADS  Article  Google Scholar 

  13. 13

    Chihhui, W. et al. Metamaterial-based integrated plasmonic absorber/emitter for solar thermo-photovoltaic systems. J. Opt. 14, 024005 (2012).

    Article  Google Scholar 

  14. 14

    Wu, C. et al. Fano-resonant asymmetric metamaterials for ultrasensitive spectroscopy and identification of molecular monolayers. Nature Mater. 11, 69–75 (2012).

    ADS  Article  Google Scholar 

  15. 15

    Kohoutek, J. et al. Integrated all-optical infrared switchable plasmonic quantum cascade laser. Nano Lett. 12, 2537–2541 (2012).

    ADS  Article  Google Scholar 

  16. 16

    Tittl, A. et al. A switchable mid-infrared plasmonic perfect absorber with multispectral thermal imaging capability. Adv. Mater. 27, 4597–4603 (2015).

    Article  Google Scholar 

  17. 17

    Luther, J. M., Jain, P. K., Ewers, T. & Alivisatos, A. P. Localized surface plasmon resonances arising from free carriers in doped quantum dots. Nature Mater. 10, 361–366 (2011).

    ADS  Article  Google Scholar 

  18. 18

    Chou, L.-W., Boyuk, D. S. & Filler, M. A. Optically abrupt localized surface plasmon resonances in Si nanowires by mitigation of carrier density gradients. ACS Nano 9, 1250–1256 (2015).

    Article  Google Scholar 

  19. 19

    Wagner, M. et al. Ultrafast dynamics of surface plasmons in InAs by time-resolved infrared nanospectroscopy. Nano Lett. 14, 4529–4534 (2014).

    ADS  Article  Google Scholar 

  20. 20

    Yan, H. et al. Damping pathways of mid-infrared plasmons in graphene nanostructures. Nature Photon. 7, 394–399 (2013).

    ADS  Article  Google Scholar 

  21. 21

    Brar, V. W., Jang, M. S., Sherrott, M., Lopez, J. J. & Atwater, H. A. Highly confined tunable mid-infrared plasmonics in graphene nanoresonators. Nano Lett. 13, 2541–2547 (2013).

    ADS  Article  Google Scholar 

  22. 22

    Wagner, M. et al. Ultrafast and nanoscale plasmonic phenomena in exfoliated graphene revealed by infrared pump–probe nanoscopy. Nano Lett. 14, 894–900 (2014).

    ADS  Article  Google Scholar 

  23. 23

    Li, S. Q. et al. Infrared plasmonics with indium–tin-oxide nanorod arrays. ACS Nano 5, 9161–9170 (2011).

    Article  Google Scholar 

  24. 24

    Lounis, S. D., Runnerstrom, E. L., Bergerud, A., Nordlund, D. & Milliron, D. J. Influence of dopant distribution on the plasmonic properties of indium tin oxide nanocrystals. J. Am. Chem. Soc. 136, 7110–7116 (2014).

    Article  Google Scholar 

  25. 25

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

    ADS  Article  Google Scholar 

  26. 26

    Granqvist, C. G. & Hultåker, A. Transparent and conducting ITO films: new developments and applications. Thin Solid Films 411, 1–5 (2002).

    ADS  Article  Google Scholar 

  27. 27

    Rhodes, C. et al. Surface plasmon resonance in conducting metal oxides. J. Appl. Phys. 100, 054905 (2006).

    ADS  Article  Google Scholar 

  28. 28

    Zhu, Y., Hu, X., Fu, Y., Yang, H. & Gong, Q. Ultralow-power and ultrafast all-optical tunable plasmon-induced transparency in metamaterials at optical communication range. Sci. Rep. 3, 2338 (2013).

    ADS  Article  Google Scholar 

  29. 29

    Abb, M., Wang, Y., de Groot, C. H. & Muskens, O. L. Hotspot-mediated ultrafast nonlinear control of multifrequency plasmonic nanoantennas. Nature Commun. 5, 4869 (2014).

    ADS  Article  Google Scholar 

  30. 30

    Gregory, S. A., Wang, Y., de Groot, C. H. & Muskens, O. L. Extreme subwavelength metal oxide direct and complementary metamaterials. ACS Photon. 2, 606–614 (2015).

    Article  Google Scholar 

  31. 31

    Li, S.-Q. et al. Ultra-sharp plasmonic resonances from monopole optical nanoantenna phased arrays. Appl. Phys. Lett. 104, 231101 (2014).

    ADS  Article  Google Scholar 

  32. 32

    Li, S.-Q. et al. Plasmonic–photonic mode coupling in indium-tin-oxide nanorod arrays. ACS Photon. 1, 163–172 (2014).

    Article  Google Scholar 

  33. 33

    Wurtz, G. A. et al. Guided plasmonic modes in nanorod assemblies: strong electromagnetic coupling regime. Opt. Express 16, 7460–7470 (2008).

    ADS  Article  Google Scholar 

  34. 34

    Bohren, C. F. & Huffman, D. R. Absorption and Scattering of Light by Small Particles (Wiley, 2007).

    Google Scholar 

  35. 35

    Hamberg, I., Granqvist, C. G., Berggren, K. F., Sernelius, B. E. & Engström, L. Band-gap widening in heavily Sn-doped In2O3 . Phys. Rev. B 30, 3240–3249 (1984).

    ADS  Article  Google Scholar 

  36. 36

    Hartland, G. V. Optical studies of dynamics in noble metal nanostructures. Chem. Rev. 111, 3858–3887 (2011).

    Article  Google Scholar 

  37. 37

    Zavelani-Rossi, M. et al. Transient optical response of a single gold nanoantenna: the role of plasmon detuning. ACS Photon. 2, 521–529 (2015).

    Article  Google Scholar 

  38. 38

    Del Fatti, N. et al. Nonequilibrium electron dynamics in noble metals. Phys. Rev. B 61, 16956–16966 (2000).

    ADS  Article  Google Scholar 

  39. 39

    Sun, C. K., Vallée, F., Acioli, L. H., Ippen, E. P. & Fujimoto, J. G. Femtosecond-tunable measurement of electron thermalization in gold. Phys. Rev. B 50, 15337–15348 (1994).

    ADS  Article  Google Scholar 

  40. 40

    Voisin, C. et al. Ultrafast electron-electron scattering and energy exchanges in noble-metal nanoparticles. Phys. Rev. B 69, 195416 (2004).

    ADS  Article  Google Scholar 

  41. 41

    Lee, H. W. et al. Nanoscale conducting oxide PlasMOStor. Nano Lett. 14, 6463–6468 (2014).

    ADS  Article  Google Scholar 

  42. 42

    Garcia, G. et al. Dynamically modulating the surface plasmon resonance of doped semiconductor nanocrystals. Nano Lett. 11, 4415–4420 (2011).

    ADS  Article  Google Scholar 

  43. 43

    Tice, D. B. et al. Ultrafast modulation of the plasma frequency of vertically aligned indium tin oxide rods. Nano Lett. 14, 1120–1126 (2014).

    ADS  Article  Google Scholar 

  44. 44

    Abb, M., Albella, P., Aizpurua, J. & Muskens, O. L. All-optical control of a single plasmonic nanoantenna–ITO hybrid. Nano Lett. 11, 2457–2463 (2011).

    ADS  Article  Google Scholar 

  45. 45

    Ruske, F. et al. Optical modeling of free electron behavior in highly doped ZnO films. Thin Solid Films 518, 1289–1293 (2009).

    ADS  Article  Google Scholar 

  46. 46

    Pisarkiewicz, T. & Kolodziej, A. Nonparabolicity of the conduction band structure in degenerate tin dioxide. Phys. Stat. Solidi B 158, K5–K8 (1990).

    ADS  Article  Google Scholar 

  47. 47

    Liu, X. et al. Quantification and impact of nonparabolicity of the conduction band of indium tin oxide on its plasmonic properties. Appl. Phys. Lett. 105, 181117 (2014).

    ADS  Article  Google Scholar 

  48. 48

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

    ADS  Article  Google Scholar 

  49. 49

    Cohen, M. H. Energy bands in the bismuth structure. I. A nonellipsoidal model for electrons in Bi. Phys. Rev. 121, 387–395 (1961).

    ADS  Article  Google Scholar 

  50. 50

    Carpene, E. Ultrafast laser irradiation of metals: Beyond the two-temperature model. Phys. Rev. B 74, 024301 (2006).

    ADS  Article  Google Scholar 

  51. 51

    Vallée, F. Non-Equilibrium Dynamics of Semiconductors and Nanostructures Ch. 5 (Taylor & Francis, 2005).

    Google Scholar 

  52. 52

    Elser, J., Wangberg, R. & Podolskiy, V. A. Nanowire metamaterials with extreme optical anisotropy. Appl. Phys. Lett. 89, 261102 (2006).

    ADS  Article  Google Scholar 

  53. 53

    Vasilantonakis, N. et al. Bulk plasmon-polaritons in hyperbolic nanorod metamaterial waveguides. Laser Photon. Rev. 9, 345–353 (2015).

    ADS  Article  Google Scholar 

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The work was funded by the MRSEC program (NSF DMR-1121262) at Northwestern University. Use of the Center for Nanoscale Materials was supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. This work made use of the EPIC facility (NUANCE Center-Northwestern University), which has received support from the MRSEC program (NSF DMR-1121262) at the Materials Research Center; the International Institute for Nanotechnology (IIN); and the State of Illinois, through the IIN. The work also used the Northwestern University Micro/Nano Fabrication Facility (NUFAB), which is supported by the State of Illinois and Northwestern University.

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P.G., R.D.S. and R.P.H.C. designed experiments. P.G. fabricated the sample, performed static measurements and conceived the non-parabolicity mediated plasma frequency. R.D.S. performed transient absorption experiments. J.B.K. and P.G. developed the theory for the plasma frequency in nonparabolic bands. P.G. analysed experimental data, performed numerical computations and wrote the manuscript. R.P.H.C. supervised the project. All authors discussed the results and contributed to writing and editing of the manuscript.

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Correspondence to Robert P. H. Chang.

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Guo, P., Schaller, R., Ketterson, J. et al. Ultrafast switching of tunable infrared plasmons in indium tin oxide nanorod arrays with large absolute amplitude. Nature Photon 10, 267–273 (2016).

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