1 / 22

Relativistic nonlinear optics in laser-plasma interaction

Relativistic nonlinear optics in laser-plasma interaction. Jyhpyng Wang. Institute of Atomic and Molecular Sciences Academia Sinica, Taiwan. National Central University, Taiwan. National Taiwan University, Taiwan. Outline. Relativistic nonlinearity in laser-plasma interaction

Télécharger la présentation

Relativistic nonlinear optics in laser-plasma interaction

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Relativistic nonlinear optics in laser-plasma interaction Jyhpyng Wang Institute of Atomic and Molecular Sciences Academia Sinica, Taiwan National Central University, Taiwan National Taiwan University, Taiwan

  2. Outline • Relativistic nonlinearity in laser-plasma interaction • Relativistic harmonic generation • Generation of intense few-cycle mid-infrared pulses • Relativistic induced birefringence

  3. 100-TW laser at Nat’l Central Univ. after focusing: • peak power:3J/30 fs =100 TW • peak intensity:1020 W/cm2 (10-m focal spot) • electric field: 3.21013 V/m(50Coulomb field in hydrogen)

  4. Hamiltonian of an electron in a laser field vector potential canonical momentum scalar potential relativistic intensity: mass increase due to quivering motion:

  5. Relativistic nonlinearity in laser plasma interaction • Relativistic effects on plasma refractive index • Wave mixing mediated by plasma waves • Relativistic nonlinearity of the Lorentz force relativistic self-phase modulation nonlinear force

  6. , , Theoretic analysis of the electron motion normalized vector and scalar potentials Lorentz force Poisson’s Equation Continuity Equation solution : known laser field Phys. Rev. A 76, 063815 (2007)

  7. Modification of the laser field Maxwell Equation nonlinear source terms (functions of ) 0- source term optical rectification 1- source term nonlinear refractive index n- source term harmonic generation

  8. Harmonic generation and optical rectification Phys. Rev. A 76, 063815 (2007) Phys. Rev. A 80, 023802 (2009)

  9. Relativistic second harmonic generation intensity dependence theory experiment density dependence fundamental beam profile 2nd harmonic beam profile E. Takahashi, et al, Phys. Rev. E 65, 016402 (2001)

  10. Relativistic optical rectification fundamental beam profile theory particle-in-cell simulation THz field fundamental beam profile THz field

  11. Generation of few-cycle intense mid-infrared pulses Phys. Rev. A 82, 063804 (2010)

  12. Nonlinear phase modulation in the bubble regime modulation of refractive index density modulation advantages: • no optical damage • large working bandwidth • high spatial coherence relativistic self-phase modulation

  13. mid-IR pulse Ge-wafer photo-switch excitation pulse mid-IR pulse pinhole mid-IR pulse A. J. Alcock and P. B. Corkum, Can. J. Phys. 57, 1280 (1979)

  14. mid-IR pulse Ge-wafer photo-switch excitation pulse mid-IR pulse pinhole mid-IR pulse A. J. Alcock and P. B. Corkum, Can. J. Phys. 57, 1280 (1979)

  15. Temporal profile of the mid-IR pulse reconstructed temporal profile photo-switch gated transmission mid-IR energy (arb. units) intensity (arb. units) delay of excitation pulse with respect to mid-IR pulse (ps) pump pulse: 205 mJ/42 fs excitation pulse: 500 mJ/38 fs plasma density: 4.1x1019 cm-3 5-mm Ge window 5-mm Ge window pulse duration X 4.6 ps 9.8 ps X~15 fs consistent with particle-in-cell simulation

  16. Comparing with simulation and theoretical estimation Estimation based on Fourier transform of the phase modulated pulse Square of the electric field of the numerically filtered mid-IR pulse 2-20 mm 6-10 mm 2-6 mm 10-20 mm Simulation: mid-IR peak power in the bubble: > 0.5 TW The mid-IR pulse is encapsulated in the low-density bubble, hence is not absorbed by the plasma. The wavelength-scale bubble ensures high spatial coherence.

  17. Relativistic induced birefringence Phys. Rev. A 83, 033801 (2011)

  18. Two-beam interaction via plasma waves Maxwell Equation nonlinear source terms (functions of ) a and a' create plasma waves of k  k' , which scatter ax into ax' . induced birefringence

  19. Comparison with particle-in-cell simulation theory simulation

  20. Summary • By solving the equation of motion for electrons under an intense laser field, one can obtain the nonlinear current density as the source of relativistic nonlinear optics. • Low-order nonlinearity (nonlinear refractive index, harmonic generation, optical rectification, induced birefringence …) can be understood well from such analysis. • The theory has been verified by experiments and 3-D particle-in-cell simulation.

  21. Core members of the 10-TW and 100-TW laser facilities Collaborators Prof. Prof. Szu-yuan Chen, Academia Sinica, Taiwan Prof. Jiunn-Yuan Lin,National Chung-Cheng Univ., Taiwan Prof. Hsu-Hsin Chu, National Central Univ., Taiwan Theoretical Analysis Prof. Gin-yih Tsaur, Tunghai Univ., Taiwan Computer Simulation Prof. Shih-Hung Chen, National Central Univ., Taiwan

  22. Thank you for your attention.

More Related