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Experimental observation of relativistic nonlinear Thomson scattering

Abstract

Classical Thomson scattering1 — the scattering of low-intensity light by electrons — is a linear process, in that it does not change the frequency of the radiation; moreover, the magnetic-field component of light is not involved. But if the light intensity is extremely high (1018 W cm−2), the electrons oscillate during the scattering process with velocities approaching the speed of light. In this relativistic regime, the effect of the magnetic and electric fields on the electron motion should become comparable, and the effective electron mass will increase. Consequently, electrons in such high fields are predicted to quiver nonlinearly, moving in figure-of-eight patterns rather than in straight lines. Scattered photons should therefore be radiated at harmonics of the frequency of the incident light2,3,4,5,6,7,8, with each harmonic having its own unique angular distribution4,5,6. Ultrahigh-peak-power lasers9 offer a means of creating the huge photon densities required to study relativistic, or ‘nonlinear’ (ref. 6), Thomson scattering. Here we use such an approach to obtain direct experimental confirmation of the theoretical predictions of relativistic Thomson scattering. In the future, it may be possible to achieve coherent10,11 generation of the harmonics, a process that could be potentially utilized for ‘table-top’ X-ray sources.

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Figure 1: Dependence of the second-harmonic light on laser intensity and plasma density.
Figure 2: Angular pattern of the second-harmonic light.
Figure 3: Angular pattern of the third-harmonic light.
Figure 4: Spectra of harmonics.

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References

  1. Thomson, J. J. Conduction of Electricity through Gases (Cambridge Univ. Press, 1906).

    MATH  Google Scholar 

  2. Vachaspati Harmonics in the scattering of light by free electrons. Phys. Rev. 128, 664–666 (1962).

  3. Brown, L. S. & Kibble, T. W. B. Interaction of intense laser beams with electrons. Phys. Rev. 133, A705–A719 (1964).

    Article  ADS  CAS  Google Scholar 

  4. Sarachik, E. S. & Schappert, G. T. Classical theory of the scattering of intense laser radiation by free electrons. Phys. Rev. D 1, 2738–2753 (1970).

    Article  ADS  Google Scholar 

  5. Castillo-Herrera, C. I. & Johnston, T. W. Incoherent harmonic emission from strong electromagnetic waves in plasmas. IEEE Trans. Plasma Sci. 21, 125–135 (1993).

    Article  ADS  CAS  Google Scholar 

  6. Esarey, E., Ride, S. K. & Sprangle, P. Nonlinear Thomson scattering of intense laser pulses from beams and plasmas. Phys. Rev. E 48, 3003–3021 (1993).

    Article  ADS  CAS  Google Scholar 

  7. Hartemann, F. V. & Luhmann, N. C. J Classical electrodynamical derivation of the radiation damping force. Phys. Rev. Lett. 74, 1107–1110 (1995).

    Article  ADS  CAS  Google Scholar 

  8. Hartemann, F. V. High-intensity scattering processes of relativistic electrons in vacuum. Phys. Plasmas 5, 2037–2047 (1998).

    Article  ADS  CAS  Google Scholar 

  9. Maine, P. et al. Generation of ultrahigh peak power pulses by chirped pulse amplification. IEEE J. Quantum Electron. 24, 398–403 (1988).

    Article  ADS  Google Scholar 

  10. Esarey, E. et al. Nonlinear analysis of relativistic harmonic generation by intense lasers in plasmas. IEEE Trans. Plasma Sci. 21, 95–104 (1993).

    Article  ADS  CAS  Google Scholar 

  11. Esarey, E. & Sprangle, P. Generation of stimulated backscattered harmonic generation from intense-laser interactions with beams and plasmas. Phys. Rev. A 45, 5872–5882 (1992).

    Article  ADS  CAS  Google Scholar 

  12. Meyer, J. & Zhu, Y. Second harmonic emission from an underdense laser-produced plasma and filamentation. Phys. Fluids 30, 890–895 (1987).

    Article  ADS  Google Scholar 

  13. Basov, N. G. et al. Investigation of 2ω0-harmonic generation in a laser plasma. Sov. Phys. JETP 49, 1059–1067 (1979).

    ADS  Google Scholar 

  14. Malka, V. et al. Second harmonic generation and its interaction with relativistic plasma waves driven by forward Raman instability in underdense plasmas. Phys. Plasmas 4, 1127–1131 (1997).

    Article  ADS  CAS  Google Scholar 

  15. Englert, T. J. & Rinehart, E. A. Second-harmonic photons from the interaction of free electrons with intense laser radiation. Phys. Rev. A 28, 1539–1545 (1983).

    Article  ADS  CAS  Google Scholar 

  16. Bula, C. et al. Observation of nonlinear effects in Compton scattering. Phys. Rev. Lett. 76, 3116–3119 (1996).

    Article  ADS  CAS  Google Scholar 

  17. Brunel, F. Harmonic generation due to plasma effects in a gas undergoing multiphoton ionization in the high-intensity limit. J. Opt. Soc. Am. B 7, 521–526 (1990).

    Article  ADS  CAS  Google Scholar 

  18. Chen, S.-Y. et al. Evolution of a plasma waveguide created during relativistic-ponderomotive self-channeling of an intense laser pulse. Phys. Rev. Lett. 80, 2610–2613 (1998).

    Article  ADS  CAS  Google Scholar 

  19. Le Blanc, S. P. et al. Temporal characterization of a self-modulated laser wakefield. Phys. Rev. Lett. 77, 5381–5384 (1996).

    Article  ADS  CAS  Google Scholar 

Download references

Acknowledgements

We thank G. Mourou, R. Wagner and X.-F. Wang for discussions. The work of S.C. and A.M. was supported by US NSF and that of D.U. by the Office of Energy Research, US DOE.

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Correspondence to Donald Umstadter.

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Chen, Sy., Maksimchuk, A. & Umstadter, D. Experimental observation of relativistic nonlinear Thomson scattering. Nature 396, 653–655 (1998). https://doi.org/10.1038/25303

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