Harmonic radiation of a relativistic nonlinear inverse Compton scattering using two laser wavelengths

oleh: Y. Sakai, O. Williams, G. Andonian, A. Fukasawa, E. Hemsing, A. Marinelli, S. Barber, F. H. O’Shea, J. B. Rosenzweig

Format: Article
Diterbitkan: American Physical Society 2011-12-01

Deskripsi

The use of two different wavelength lasers in the nonlinear regime of the inverse Compton scattering interaction is proposed in order to provide a new strategy for controlling scattered photon energy distributions in the x-ray to γ-ray spectral region. In this nonlinear interaction, the component of the relativistic electron’s trajectory driven by a longer-wavelength laser with the normalized vector potential a_{L}∼1 is a large oscillatory figure-8; in the proposed scenario a rapid small-amplitude oscillation induced by a shorter-wavelength laser is superimposed upon this figure-8. Thus, the electron’s momentum is mainly supplied from longer-wavelength laser, while the high-frequency part of the acceleration is given by shorter-wavelength laser. In this way, the harmonics radiated at high frequency from the oscillating electron can be strongly modified by the nonlinear motion initiated by the low frequency, large a_{L} laser resulting in the generation of the harmonics with the photon energy of 4γ^{2}h̵(ω_{L,short}+nω_{L,long}). In this paper, the electron’s kinetics in the two-wavelength laser field and the concomitant emitted radiation spectrum are examined, with numerical illustrations based on a classical Lienard-Wiechert potential formalism provided.