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Photoresponse of a strongly correlated material determined by scanning photocurrent microscopy

Nature Nanotechnology volume 7, pages 723–727 (2012)Cite this article

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Abstract

The generation of a current by light is a key process in optoelectronic and photovoltaic devices. In band semiconductors, depletion fields associated with interfaces separate long-lived photo-induced carriers. However, in systems with strong electron–electron and electron–phonon correlations it is unclear what physics will dominate the photoresponse. Here, we investigate photocurrent in VO2, an exemplary strongly correlated material known for its dramatic metal–insulator transition1,2,3 at Tc ≈ 68 °C, which could be useful for optoelectronic detection and switching up to ultraviolet wavelengths4,5,6,7,8,9,10. Using scanning photocurrent microscopy on individual suspended VO2 nanobeams we observe a photoresponse peaked at the metal–insulator boundary but extending throughout both insulating and metallic phases. We determine that the response is photothermal, implying efficient carrier relaxation to a local equilibrium in a manner consistent with strong correlations11,12,13,14. Temperature-dependent measurements reveal subtle phase changes within the insulating state. We further demonstrate switching of the photocurrent by optical control of the metal–insulator boundary arrangement. Our work shows the value of applying scanning photocurrent microscopy to nanoscale crystals in the investigation of strongly correlated materials, and the results are relevant for designing and controlling optoelectronic devices employing such materials.

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Figure 1: SPCM on a suspended VO2 nanobeam device.
Figure 2: Photocurrent measurements at temperatures across the MIT.
Figure 3: Evidence for the thermoelectric origin of the photocurrent.
Figure 4: Optical control of the photocurrent and imaging the evolution of the insulating phase.

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References

  1. Morin, F. J. Oxides which show a metal-to-insulator transition at the Neel temperature. Phys. Rev. Lett. 3, 34–36 (1959).

    Article  CAS  Google Scholar 

  2. Zylbersztejn, A. & Mott, N. F. Metal–insulator transition in vanadium dioxide. Phys. Rev. B 11, 4383–4395 (1975).

    Article  CAS  Google Scholar 

  3. Eyert, V. The metal–insulator transitions of VO2: a band theoretical approach. Ann. Phys. Berlin 11, 650–702 (2002).

    Article  CAS  Google Scholar 

  4. Verleur, H. W., Barker, A. S. & Berglund, C. N. Optical properties of VO2 between 0.25 and 5 eV. Phys. Rev. 172, 788–798 (1968).

    Article  CAS  Google Scholar 

  5. Driscoll, T. et al. Dynamic tuning of an infrared hybrid-metamaterial resonance using vanadium dioxide. Appl. Phys. Lett. 93, 024101 (2008).

    Article  Google Scholar 

  6. Becker, M. F., Buckman, A. B. & Walser, R. M. Femtosecond laser excitation of the semiconductor–metal phase transition in VO2 . Appl. Phys. Lett. 65, 1507–1509 (1994).

    Article  CAS  Google Scholar 

  7. Rini, M. et al. Optical switching in VO2 films by below-gap excitation. Appl. Phys. Lett. 92, 181904 (2008).

    Article  Google Scholar 

  8. Cavalleri, A., Rini, M. & Schoenlein, R. W. Ultra-broadband femtosecond measurements of the photo-induced phase transition in VO2: from the mid-IR to the hard X-rays. J. Phys. Soc. Jpn 75, 011004 (2006).

    Article  Google Scholar 

  9. Hilton, D. J. et al. Enhanced photosusceptibility near Tc for the light-induced insulator-to-metal phase transition in vanadium dioxide. Phys. Rev. Lett. 99, 226401 (2007).

    Article  CAS  Google Scholar 

  10. Kubler, C. et al. Coherent structural dynamics and electronic correlations during an ultrafast insulator-to-metal phase transition in VO2 . Phys. Rev. Lett. 99, 116401 (2007).

    Article  CAS  Google Scholar 

  11. Wentzcovitch, R. M., Schulz, W. W. & Allen, P. B. VO2: Peierls or Mott–Hubbard? A view from band theory. Phys. Rev. Lett. 72, 3389–3392 (1994).

    Article  CAS  Google Scholar 

  12. Rice, T. M., Launois, H. & Pouget, J. P. Comment on ‘VO2: Peierls or Mott–Hubbard? A view from band theory'. Phys. Rev. Lett. 73, 3042 (1994).

    Article  CAS  Google Scholar 

  13. Kim, H. T. et al. Monoclinic and correlated metal phase in VO2 as evidence of the Mott transition: coherent phonon analysis. Phys. Rev. Lett. 97, 266401 (2006).

    Article  Google Scholar 

  14. Kim, B-J. et al. Micrometer X-ray diffraction study of VO2 films: separation between metal–insulator transition and structural phase transition. Phys. Rev. B 77, 235401 (2008).

    Article  Google Scholar 

  15. Lopez, R., Feldman, L. C. & Haglund, R. F. Jr Size-dependent optical properties of VO2 nanoparticle arrays. Phys. Rev. Lett. 93, 177403 (2004).

    Article  CAS  Google Scholar 

  16. Guiton, B. S., Gu, Q., Prieto, A. L., Gudiksen, M. S. & Park, H. Single-crystalline vanadium dioxide nanowires with rectangular cross sections. J. Am. Chem. Soc. 127, 498–499 (2005).

    Article  CAS  Google Scholar 

  17. Wu, J. Q. et al. Strain-induced self organization of metal–insulator domains in single-crystalline VO2 nanobeams. Nano Lett. 6, 2313–2317 (2006).

    Article  CAS  Google Scholar 

  18. Wei, J., Wang, Z. H., Chen, W. & Cobden, D. H. New aspects of the metal–insulator transition in single-domain vanadium dioxide nanobeams. Nature Nanotech. 4, 420–424 (2009).

    Article  CAS  Google Scholar 

  19. Cao, J. et al. Strain engineering and one-dimensional organization of metal–insulator domains in single-crystal vanadium dioxide beams. Nature Nanotech. 4, 732–737 (2009).

    Article  CAS  Google Scholar 

  20. Cao, J. et al. Constant threshold resistivity in the metal–insulator transition of VO2 . Phys. Rev. B 82, 241101 (2010).

    Article  Google Scholar 

  21. Cao, J. et al. Extended mapping and exploration of the vanadium dioxide stress–temperature phase diagram. Nano Lett. 10, 2667–2673 (2010).

    Article  CAS  Google Scholar 

  22. Zhang, S. X., Chou, J. Y. & Lauhon, L. J. Direct correlation of structural domain formation with the metal insulator transition in a VO2 nanobeam. Nano Lett. 9, 4527–4532 (2009).

    Article  CAS  Google Scholar 

  23. Tselev, A. et al. Symmetry relationship and strain-induced transitions between insulating M1 and M2 and metallic R phases of vanadium dioxide. Nano Lett. 10, 4409–4416 (2010).

    Article  CAS  Google Scholar 

  24. Sohn, J. I. et al. Surface-stress-induced Mott transition and nature of associated spatial phase transition in single crystalline VO2 nanowires. Nano Lett. 9, 3392–3397 (2009).

    Article  CAS  Google Scholar 

  25. Jones, A. C., Berweger, S., Wei, J., Cobden, D. & Raschke, M. B. Nano-optical investigations of the metal–insulator phase behavior of individual VO2 microcrystals. Nano Lett. 10, 1574–1581 (2010).

    Article  CAS  Google Scholar 

  26. Liu, W. T. et al. Intrinsic optical properties of vanadium dioxide near the insulator–metal transition. Nano Lett. 11, 466–470 (2011).

    Article  CAS  Google Scholar 

  27. Cao, J., Fan, W., Zheng, H. & Wu, J. Thermoelectric effect across the metal–insulator domain walls in VO2 microbeams. Nano Lett. 9, 4001–4006 (2009).

    Article  CAS  Google Scholar 

  28. Marezio, M., McWhan, B., Dernier, P. D. & Remeika, J. P. Structural aspects of metal–insulator transitions in Cr-doped VO2 . Phys. Rev. B 5, 2541–2551 (1972).

    Article  Google Scholar 

  29. Berglund, C. N. & Guggenheim, H. J. Electronic properties of VO2 near the semiconductor–metal transition. Phys. Rev. 185, 1022–1033 (1969).

    Article  CAS  Google Scholar 

  30. Oh, D. W., Ko, C., Ramanathan, S. & Cahill, D. G. Thermal conductivity and dynamic heat capacity across the metal–insulator transition in thin film VO2 . Appl. Phys. Lett. 96, 151906 (2010).

    Article  Google Scholar 

  31. Graham, R., Miller, C., Triplett, M. & Yu, D. Scanning photocurrent microscopy in single nanowire devices. Proc. SPIE 8106, 81060–81061 (2011).

    Article  Google Scholar 

  32. Miller, C. et al. Unusually long free carrier lifetime and metal–insulator band offset in vanadium dioxide. Phys. Rev. B 85, 085111 (2012).

    Article  Google Scholar 

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Acknowledgements

This work was supported by the US Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering (award DE-SC0002197), by the Army Research Office (contract 48385-PH) and by an NSF Career Award (DMR-1150719, to X.X.). The authors thank B. Spivak for helpful discussions.

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Authors and Affiliations

  1. Department of Physics, University of Washington, Seattle, 98195, Washington, USA

    T. Serkan Kasırga, Dong Sun, Jae H. Park, Jim M. Coy, Zaiyao Fei, Xiaodong Xu & David H. Cobden

  2. Department of Materials Science and Engineering, University of Washington, Seattle, 98195, Washington, USA

    Xiaodong Xu

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  1. T. Serkan Kasırga
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All authors participated in the experiments, discussed the results, commented on the manuscript, and made critical contributions to the work.

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Correspondence to Xiaodong Xu or David H. Cobden.

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Kasırga, T., Sun, D., Park, J. et al. Photoresponse of a strongly correlated material determined by scanning photocurrent microscopy. Nature Nanotech 7, 723–727 (2012). https://doi.org/10.1038/nnano.2012.176

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