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Novel electrical switching behaviour and logic in carbon nanotube Y-junctions


Carbon-nanotube-based electronics offers significant potential as a nanoscale alternative to silicon-based devices for molecular electronics technologies. Here, we show evidence for a dramatic electrical switching behaviour in a Y-junction carbon-nanotube1,2,3 morphology. We observe an abrupt modulation of the current from an on- to an off-state, presumably mediated by defects and the topology of the junction. The mutual interaction of the electron currents4 in the three branches of the Y-junction is shown to be the basis for a potentially new logic device. This is the first time that such switching and logic functionalities have been experimentally demonstrated in Y-junction nanotubes without the need for an external gate. A class of nanoelectronic architecture and functionality, which extends well beyond conventional field-effect transistor technologies5,6, is now possible.

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Figure 1: The CNT Y-junction morphology and experimental arrangement for measuring transport properties.
Figure 2: Current (I)–voltage (V) characteristics of a Y-junction.
Figure 3: Observation of near-perfect electrical switching in Y-junctions.
Figure 4: Frequency response of the switching characteristic in the Y-junction.
Figure 5: The CNT Y-junction for logic applications.


  1. Zhou, D. & Seraphin, S. Complex branching phenomena in the growth of carbon nanotubes. Chem. Phys. Lett. 238, 286–289 (1995).

    Article  Google Scholar 

  2. Li, W. Z., Wen, J. G. & Ren, Z. F. Straight carbon nanotube Y junctions. Appl. Phys. Lett. 79, 1879–1881 (2001).

    Article  Google Scholar 

  3. Satishkumar, B. C., Thomas, P. J., Govindaraj, A. & Rao, C. N. R. Y-junction carbon nanotubes. Appl. Phys. Lett. 77, 2530–2532 (2000).

    Article  Google Scholar 

  4. Xu, H. Q. Electrical properties of three-terminal ballistic junctions. Appl. Phys. Lett. 78, 2064–2066 (2001).

    Article  Google Scholar 

  5. Xu, H. Q. et al. Novel nanoelectronic triodes and logic devices with TBJs. IEEE Electron Dev. Lett. 25, 164–166 (2004).

    Article  Google Scholar 

  6. Baughman, R. H., Zakhidov, A. A. & de Heer, W. A. Carbon nanotubes-the route toward applications. Science 297, 787–792 (2002).

    Article  Google Scholar 

  7. Saito, R., Dresselhaus, G. & Dresselhaus, M. S. Physical Properties of Carbon Nanotubes (Imperial College Press, London, 1998).

    Book  Google Scholar 

  8. Forro, L. & Schonenberger, C. in Carbon Nanotubes-Topics in Applied Physics (ed. Avouris, P.) (Springer, Heidelberg, 2001).

    Google Scholar 

  9. Kim, P., Shi, L., Majumdar, A. & McEuen, P. L. Thermal transport measurements of individual multiwalled nanotubes. Phys. Rev. Lett. 87, 215502 (2001).

    Article  Google Scholar 

  10. Collins, P. G., Hersam, M., Arnold, M., Martel, R. & Avouris, P. Current saturation and electrical breakdown in mutiwalled carbon nanotubes. Phys. Rev. Lett. 86, 3128–3131 (2001).

    Article  Google Scholar 

  11. Martel, R., Schmidt, T., Shea, H. R., Hertel, T. & Avouris, P. Single- and multi-wall carbon nanotube field-effect transistors. Appl. Phys. Lett. 73, 2447–2449 (1998).

    Article  Google Scholar 

  12. Tans, S. J., Verschueren, A. R. M. & Dekker, C. Room-temperature transistor based on a single carbon nanotube. Nature 393, 49–52 (1998).

    Article  Google Scholar 

  13. Javey, A., Guo, J., Wang, Q., Lundstrom, M. & Dai, H. Ballistic carbon nanotube field-effect transistors. Nature 424, 654–657 (2003).

    Article  Google Scholar 

  14. Postma, H. W. C., Teepen, T., Yao, Z., Grifoni, M. & Dekker, C. Carbon nanotube single-electron transistors at room temperature. Science 293, 76–79 (2001).

    Article  Google Scholar 

  15. Gothard, N. et al. Controlled growth of Y-junction nanotubes using Ti-doped vapor catalyst. Nano Lett. 4, 213–217 (2004).

    Article  Google Scholar 

  16. Shorubalko, I., Xu, H. Q., Omling, P. & Samuelson, L. Tunable nonlinear current-voltage characteristics of three-terminal ballistic nanojunctions. Appl. Phys. Lett. 83, 2369–2371 (2003).

    Article  Google Scholar 

  17. Shorubalko, I. et al. A novel frequency-multiplication device based on three-terminal ballistic junction. IEEE Electron Dev. Lett. 23, 377–379 (2002).

    Article  Google Scholar 

  18. Song, A. M. et al. Nonlinear electron transport in an asymmetric microjunction: A ballistic rectifier. Phys. Rev. Lett. 80, 3831–3834 (1998).

    Article  Google Scholar 

  19. Palm, T. & Thylen, L. Designing logic functions using an electron waveguide Y-branch switch. J. Appl. Phys. 79, 8076–8081 (1996).

    Article  Google Scholar 

  20. Andriotis, A. N., Menon, M., Srivastava, D. & Chernozatonski, L. Transport properties of single-wall carbon nanotube Y-junctions. Phys. Rev. B 65, 165416 (2002).

    Article  Google Scholar 

  21. Csontos, D. & Xu, H. Q. Quantum effects in the transport properties of nanoelectronic three-terminal Y-junction devices. Phys. Rev. B 67, 235322 (2003).

    Article  Google Scholar 

  22. Andriotis, A. N., Srivastava, D. & Menon, M. Comment on “Intrinsic electron transport properties of carbon nanotube Y-junctions”. Appl. Phys. Lett. 83, 1674–1675 (2003).

    Article  Google Scholar 

  23. Tian, W. et al. Conductance spectra of molecular wires. J. Chem. Phys. 109, 2874–2882 (1998).

    Article  Google Scholar 

  24. Heinze, S. et al. Carbon nanotubes as Schottky barrier transistors. Phys. Rev. Lett. 89, 106801 (2002).

    Article  Google Scholar 

  25. Crespi, V. H., Chopra, N. G., Cohen, M. L., Zettl, A. & Louie, S. G. Anisotropic electron-beam damage and the collapse of carbon nanotubes. Phys. Rev. B 54, 5927–5931 (1996).

    Article  Google Scholar 

  26. Banhart, F. Irradiation effects in carbon nanostructures. Rep. Prog. Phys. 62, 1181–1221 (1999).

    Article  Google Scholar 

  27. Gopal, V. et al. Rapid prototyping of site-specific nanocontacts by electron and ion beam assisted direct-write nanolithography. Nano Lett. 4, 2059–2063 (2004).

    Article  Google Scholar 

  28. Bachtold, A. et al. Contacting carbon nanotubes selectively with low-ohmic contacts for four-probe electric measurements. Appl. Phys. Lett. 73, 274–276 (1998).

    Article  Google Scholar 

  29. Andriotis, A. N., Menon, M., Srivastava, D. & Chernozatonski, L. Rectification properties of carbon nanotube “Y-junctions”. Phys. Rev. Lett. 87, 066802 (2001).

    Article  Google Scholar 

  30. Papadapoulos, C., Rakitin, A., Li, J., Vedeneev, A. S. & Xu, J. M. Electronic transport in Y-junction carbon nanotubes. Phys. Rev. Lett. 85, 3476–3479 (2000).

    Article  Google Scholar 

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P.R.B. acknowledges useful discussions with M. Di Ventra and J. Lagerkvist. We also thank graduate students N. Gothard and J. Gaillard for synthesizing the Y-junction nanotubes, and P. Yu who set up the LabView programs for data acquisition. We acknowledge the support of the work by NSF-NIRTs under Grant numbers DMI-0210559, DMI-0303790, DMI-0304019 and University of California Discovery Fund under Grant No. ele02-10133/Jin.

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Correspondence to P. R. Bandaru.

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Bandaru, P., Daraio, C., Jin, S. et al. Novel electrical switching behaviour and logic in carbon nanotube Y-junctions. Nature Mater 4, 663–666 (2005).

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