Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

A carbon-nanotube-based electron source with a 0.3-eV energy spread and an unconventional time delay

Nature Materials (2025)Cite this article

Subjects

Abstract

Conventional metal-tip-based laser-driven electron sources are normally constrained by a trade-off between energy spread and pulse width due to optical-field-induced free electron acceleration. This makes it challenging to surpass the current state-of-the-art, which exhibits energy spreads exceeding 1 eV and pulse durations of hundreds of femtoseconds. Here we report an unconventional delayed emission from a one-dimensional carbon-nanotube-based electron source. By utilizing a special pump–probe approach, we apply 7-fs laser pulses to the carbon-nanotube emitters and observe free electron emission tens of femtoseconds after the pulse. This delayed emission results in a substantially reduced energy spread of approximately 0.3 eV and an electron pulse width of about 13 fs. Through time-dependent density functional theory calculations, we find that the delayed emission is driven by the interplay of collective oscillations and electron–electron interactions. Our results may provide a promising technology for developing cutting-edge ultrafast electron sources.

Access through your institution
Buy or subscribe

This is a preview of subscription content, access via your institution

Access options

Access through your institution

Buy this article

  • Purchase on SpringerLink
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Seven-femtosecond laser-driven monochromatic emission.
Fig. 2: Sampling of the electronic signal on the emitting tip.
Fig. 3: Measurement of emission timing.

Similar content being viewed by others

Data availability

All data are available in the Supplementary Information. Source data are provided with this paper.

References

  1. Barwick, B., Flannigan, D. J. & Zewail, A. H. Photon-induced near-field electron microscopy. Nature 462, 902–906 (2009).

    Article  CAS  PubMed  Google Scholar 

  2. Zewail, A. H. Four-dimensional electron microscopy. Science 328, 187–193 (2010).

    Article  CAS  PubMed  Google Scholar 

  3. Hassan, M. T., Baskin, J. S., Liao, B. & Zewail, A. H. High-temporal-resolution electron microscopy for imaging ultrafast electron dynamics. Nat. Photonics 11, 425–430 (2017).

    Article  CAS  Google Scholar 

  4. Kurman, Y. et al. Spatiotemporal imaging of 2D polariton wave packet dynamics using free electrons. Science 372, 1181–1186 (2021).

    Article  CAS  PubMed  Google Scholar 

  5. Gulde, M. et al. Ultrafast low-energy electron diffraction in transmission resolves polymer/graphene superstructure dynamics. Science 345, 200–204 (2014).

    Article  CAS  PubMed  Google Scholar 

  6. Priebe, K. E. et al. Attosecond electron pulse trains and quantum state reconstruction in ultrafast transmission electron microscopy. Nat. Photonics 11, 793–797 (2017).

    Article  CAS  Google Scholar 

  7. Domroese, T. et al. Light-induced hexatic state in a layered quantum material. Nat. Mater. 22, 1345–1351 (2023).

    Article  CAS  Google Scholar 

  8. Horstmann, J. G. et al. Coherent control of a surface structural phase transition. Nature 583, 232–234 (2020).

    Article  CAS  PubMed  Google Scholar 

  9. Danz, T., Domrose, T. & Ropers, C. Ultrafast nanoimaging of the order parameter in a structural phase transition. Science 371, 371–374 (2021).

    Article  CAS  PubMed  Google Scholar 

  10. Kim, H. et al. Attosecond field emission. Nature 613, 662–666 (2023).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  11. Dienstbier, P. et al. Tracing attosecond electron emission from a nanometric metal tip. Nature 616, 702–706 (2023).

    Article  CAS  PubMed  Google Scholar 

  12. Herink, G., Solli, D. R., Gulde, M. & Ropers, C. Field-driven photoemission from nanostructures quenches the quiver motion. Nature 483, 190–193 (2012).

    Article  CAS  PubMed  Google Scholar 

  13. Krueger, M., Schenk, M. & Hommelhoff, P. Attosecond control of electrons emitted from a nanoscale metal tip. Nature 475, 78–81 (2011).

    Article  CAS  Google Scholar 

  14. Corkum, P. B. Plasma perspective on strong-field multiphoton ionization. Phys. Rev. Lett. 71, 1994–1997 (1993).

    Article  CAS  PubMed  Google Scholar 

  15. Paulus, G. G., Becker, W. & Walther, H. Classical rescattering effects in 2-color above-threshold ionization. Phys. Rev. A 52, 4043–4053 (1995).

    Article  CAS  PubMed  Google Scholar 

  16. Bormann, R., Gulde, M., Weismann, A., Yalunin, S. V. & Ropers, C. Tip-enhanced strong-field photoemission. Phys. Rev. Lett. 105, 147601 (2010).

    Article  CAS  PubMed  Google Scholar 

  17. Yanagisawa, H. et al. Optical control of field-emission sites by femtosecond laser pulses. Phys. Rev. Lett. 103, 257603 (2009).

    Article  PubMed  Google Scholar 

  18. Hommelhoff, P., Sortais, Y., Aghajani-Talesh, A. & Kasevich, M. A. Field emission tip as a nanometer source of free electron femtosecond pulses. Phys. Rev. Lett. 96, 077401 (2006).

    Article  PubMed  Google Scholar 

  19. Ropers, C., Solli, D. R., Schulz, C. P., Lienau, C. & Elsaesser, T. Localized multiphoton emission of femtosecond electron pulses from metal nanotips. Phys. Rev. Lett. 98, 043907 (2007).

    Article  CAS  PubMed  Google Scholar 

  20. Musumeci, P. et al. Multiphoton photoemission from a copper cathode illuminated by ultrashort laser pulses in an RF photoinjector. Phys. Rev. Lett. 104, 084801 (2010).

    Article  CAS  PubMed  Google Scholar 

  21. Shafir, D. et al. Resolving the time when an electron exits a tunnelling barrier. Nature 485, 343–346 (2012).

    Article  CAS  PubMed  Google Scholar 

  22. Pedatzur, O. et al. Attosecond tunnelling interferometry. Nat. Phys. 11, 815–819 (2015).

    Article  CAS  Google Scholar 

  23. Nabben, D., Kuttruff, J., Stolz, L., Ryabov, A. & Baum, P. Attosecond electron microscopy of sub-cycle optical dynamics. Nature 619, 63–67 (2023).

    Article  CAS  PubMed  Google Scholar 

  24. Schenk, M., Krueger, M. & Hommelhoff, P. Strong-field above-threshold photoemission from sharp metal tips. Phys. Rev. Lett. 105, 257601 (2010).

    Article  PubMed  Google Scholar 

  25. Li, C. et al. Extreme nonlinear strong-field photoemission from carbon nanotubes. Nat. Commun. 10, 4891 (2019).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  26. Li, C. et al. Carbon nanotubes as an ultrafast emitter with a narrow energy spread at optical frequency. Adv. Mater. 29, 1701580 (2017).

    Article  Google Scholar 

  27. De Jonge, N. et al. High brightness electron beam from a multi-walled carbon nanotube. Nature 420, 393–395 (2002).

    Article  PubMed  Google Scholar 

  28. De Jonge, N. & Bonard, J. M. Carbon nanotube electron sources and applications. Philos. Trans. R. Soc. Lond. A 362, 2239–2266 (2004).

    Article  Google Scholar 

  29. Saito, Y. & Uemura, S. Field emission from carbon nanotubes and its application to electron sources. Carbon 38, 169–182 (2000).

    Article  CAS  Google Scholar 

  30. Achermann, M., Bartko, A. P., Hollingsworth, J. A. & Klimov, V. I. The effect of Auger heating on intraband carrier relaxation in semiconductor quantum rods. Nat. Phys. 2, 557–561 (2006).

    Article  CAS  Google Scholar 

  31. Keldysh, L. Ionization in the field of a strong electromagnetic wave. Sov. Phys. JETP 20, 1307–1314 (1965).

    Google Scholar 

  32. Bunkin, F. & Fedorov, M. Cold emission of electrons from the surface of a metal in a strong radiation field. Sov. Phys. JETP 21, 896 (1965).

    Google Scholar 

  33. Zhang, P. & Lau, Y. Y. Ultrafast strong-field photoelectron emission from biased metal surfaces: exact solution to time-dependent Schrödinger equation. Sci. Rep. 6, 19894 (2016).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  34. Piglosiewicz, B. et al. Carrier-envelope phase effects on the strong-field photoemission of electrons from metallic nanostructures. Nat. Photonics 8, 37–42 (2014).

    Article  CAS  Google Scholar 

  35. Bionta, M. R. et al. On-chip sampling of optical fields with attosecond resolution. Nat. Photonics 15, 456–460 (2021).

    Article  CAS  Google Scholar 

  36. Tan, S. J., Argondizzo, A., Wang, C., Cui, X. F. & Petek, H. Ultrafast multiphoton thermionic photoemission from graphite. Phys. Rev. X 7, 011004 (2017).

    Google Scholar 

  37. Liu, K. H. et al. Quantum-coupled radial-breathing oscillations in double-walled carbon nanotubes. Nat. Commun. 4, 1375 (2013).

    Article  PubMed  Google Scholar 

  38. Kresse, G. & Furthmüller, J. Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. Phys. Rev. B 54, 11169 (1996).

    Article  CAS  Google Scholar 

  39. Perdew, J. P., Burke, K. & Ernzerhof, M. Generalized gradient approximation made simple. Phys. Rev. Lett. 77, 3865 (1996).

    Article  CAS  PubMed  Google Scholar 

  40. Andrade, X. et al. Real-space grids and the Octopus code as tools for the development of new simulation approaches for electronic systems. Phys. Chem. Chem. Phys. 17, 31371–31396 (2015).

    Article  CAS  PubMed  Google Scholar 

  41. Onida, G., Reining, L. & Rubio, A. Electronic excitations: density-functional versus many-body Green’s-function approaches. Rev. Mod. Phys. 74, 601 (2002).

    Article  CAS  Google Scholar 

  42. D’Agosta, R. & Vignale, G. Relaxation in time-dependent current-density-functional theory. Phys. Rev. Lett. 96, 016405 (2006).

    Article  PubMed  Google Scholar 

  43. Hartwigsen, C., Gœdecker, S. & Hutter, J. Relativistic separable dual-space Gaussian pseudopotentials from H to Rn. Phys. Rev. B 58, 3641 (1998).

    Article  CAS  Google Scholar 

  44. De Giovannini, U., Larsen, A. H. & Rubio, A. Modeling electron dynamics coupled to continuum states in finite volumes with absorbing boundaries. Eur. Phys. J. B 88, 56 (2015).

    Article  Google Scholar 

  45. Wang, F. et al. The optical resonances in carbon nanotubes arise from excitons. Science 308, 838–841 (2005).

    Article  CAS  PubMed  Google Scholar 

  46. Maultzsch, J. et al. Exciton binding energies in carbon nanotubes from two-photon photoluminescence. Phys. Rev. B 72, 241402 (2005).

    Article  Google Scholar 

Download references

Acknowledgements

We acknowledge funding from the National Key Research and Development Program of China (grant numbers 2022YFA1204200 (C.L.), 2021YFC2802000 (Z.L.), 2023YFF0723800 (C.L.), 2022YFA1604301 (R.L.), 2022YFA1403601 (X. Wan)), the Natural Science Foundation of China (grant numbers 52222207 (C.L.), 5225000143 (C.L.), 52372141 (Z.L.), 52302170 (A. Wang), 12174195 (C.Y.), 12188101 (X. Wan), 12234020 (X. Wang), 12450403 (X. Wang), 12425411 (R.L.) and 12434013 (C.Y.)), the Young Scientist Basic Research Program of CAS (YSBR-091 (C.L.)), the Fundamental Research Funds for the Central Universities (grant number 30922010104 (R.L.)), the National University of Defense Technology Research Fund Project (J.D.), and the Science and Technology Innovation Program of Hunan Province (grant number 2021RC4026 (J.D.)). We thank C. Ropers and P. Tang for valuable discussions.

Author information

Author notes

  1. These authors contributed equally: Ke Chen, Chao Yu, Xiaowei Wang.

Authors and Affiliations

  1. CAS Key Laboratory of Nanophotonic Materials and Devices, National Center for Nanoscience and Technology, Beijing, China

    Ke Chen, Yusong Qu, Aiwei Wang, Zhenjun Li & Chi Li

  2. Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, China

    Ke Chen, Yusong Qu, Aiwei Wang, Zhenjun Li & Chi Li

  3. Institute of Ultrafast Optical Physics, Department of Applied Physics and MIIT Key Laboratory of Semiconductor Microstructure and Quantum Sensing, Nanjing University of Science and Technology, Nanjing, China

    Chao Yu & Ruifeng Lu

  4. College of Science, Hunan Key Laboratory of Extreme Matter and Applications, Hunan Research Center of the Basic Discipline for Physical States, National University of Defense Technology, Changsha, China

    Xiaowei Wang, Li Wang, Fan Xiao & Jiayu Dai

  5. Institute of Information Functional Materials, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai, China

    Shenghan Zhou & Qing Dai

  6. National Laboratory of Solid-State Microstructures and School of Physics, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China

    Xiangang Wan

Authors
  1. Ke Chen
    View author publications

    Search author on:PubMed Google Scholar

  2. Chao Yu
    View author publications

    Search author on:PubMed Google Scholar

  3. Xiaowei Wang
    View author publications

    Search author on:PubMed Google Scholar

  4. Shenghan Zhou
    View author publications

    Search author on:PubMed Google Scholar

  5. Li Wang
    View author publications

    Search author on:PubMed Google Scholar

  6. Yusong Qu
    View author publications

    Search author on:PubMed Google Scholar

  7. Aiwei Wang
    View author publications

    Search author on:PubMed Google Scholar

  8. Fan Xiao
    View author publications

    Search author on:PubMed Google Scholar

  9. Zhenjun Li
    View author publications

    Search author on:PubMed Google Scholar

  10. Chi Li
    View author publications

    Search author on:PubMed Google Scholar

  11. Jiayu Dai
    View author publications

    Search author on:PubMed Google Scholar

  12. Xiangang Wan
    View author publications

    Search author on:PubMed Google Scholar

  13. Ruifeng Lu
    View author publications

    Search author on:PubMed Google Scholar

  14. Qing Dai
    View author publications

    Search author on:PubMed Google Scholar

Contributions

Q.D. and C.L. conceived the experiments. K.C., S.Z. and Z.L. prepared the as-grown samples and performed the characterization. K.C., Y.Q. and A.W. assembled the CNT tips. K.C., X. Wang, Y.Q., L.W. and F.X. conducted the 7-fs laser measurements. C.L. and K.C. solved the experimental data. C.Y. and R.L. conducted the TDDFT calculations. Q.D., X. Wan and J.D. helped in analysing the data and organizing the figures. Q.D., C.L., R.L., X. Wan and J.D. wrote the paper. All authors discussed the results and commented on the paper.

Corresponding authors

Correspondence to Chi Li, Jiayu Dai, Xiangang Wan, Ruifeng Lu or Qing Dai.

Ethics declarations

Competing interests

The authors declare no competing interests.

Peer review

Peer review information

Nature Materials thanks O. J. (Jom) Luiten, Shijing Tan and Peng Zhang for their contribution to the peer review of this work.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary Figs. 1–11 and Table 1.

Source data

Source Data Fig. 1

Unprocessed western blots.

Source Data Fig. 2

Unprocessed western blots.

Source Data Fig. 3

Unprocessed western blots.

Rights and permissions

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Chen, K., Yu, C., Wang, X. et al. A carbon-nanotube-based electron source with a 0.3-eV energy spread and an unconventional time delay. Nat. Mater. (2025). https://doi.org/10.1038/s41563-025-02279-7

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1038/s41563-025-02279-7

This article is cited by

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing