On electron acceleration by plane transverse electromagnetic pulses in vacuum

Abstract

The longitudinal acceleration of electrons by the transverse electromagnetic field of laser pulses of definite shapes is studied. It is shown that already a pulse of the length of a half wavelength from a CO2 laser is sufficient to accelerate an electron to energies up to the order of TeV if intensities of 1022 W/cm2 are applied. Various aspects of the electron acceleration by this method are discussed.

Short-range wakefields generated in the blowout regime of plasma-wakefield acceleration

“…Eqs. (4)- (9) are simplified in the case of axial symmetry when the three components of the electromagnetic field, E z = ∂ ξ ψ, E r = −∂ r ψ and B θ , together with ψ, depend on ξ and r = x 2 + y 2 . The equations of motion (4) reduces to…”

“…The crossing changes both the transverse and longitudinal velocities, however, one can neglect the transverse displacement of plasma electrons and consider the crossing as occurring at a fixed value of r. The problem then reduces to the relativistic motion of plasma electrons in the field that depends only on one coordinate ξ. The solution to this problem is well known [8,9]; for the reader's convenience we reproduce it in Appendix A. The vector potential A in Appendix A for our case has only radial components A r .…”

Electron Acceleration by a Laser Pulse with a Rising Propagation Speed

“…Electron acceleration by lasers without plasma effects has the advantage that well-known difficulties of instability and detuning due to plasma properties can be avoided. The first clear experimental demonstration of this type of acceleration was by Malka et al (1997), where the identical theoretical formulations of that by Scheid and Hora (1989) were demonstrated. Recently, it has also been found by numerical simulation that the electron can be captured and violently accelerated by an extra-intense laser beam with Q 0 > ∼ 100 (Q 0 = eE 0 /m e ωc) (Wang et al 1998), which is a breakthrough in laser-driven electron acceleration in a vacuum, and is of potential interest to far-field laser acceleration.…”

“…There is a basic difference between acceleration in a laser field which includes plasma effects and acceleration without a plasma. The latter is called 'acceleration in vacuum ' (Hora 1988;Cicchitelli and Hora 1990;Scheid and Hora 1989;Häuser, Scheid and Hora 1994), or 'free-wave acceleration' (Woodworth et al 1996). Electron acceleration by lasers without plasma effects has the advantage that well-known difficulties of instability and detuning due to plasma properties can be avoided.…”

Superstrong field science

“…If the pulse quickly diffracts before the full interaction, say over the Rayleigh length, p x is simply proportional to EQ. Now let us imagine, for the moment, that the laser has only half the period (unipolar) [16] or subcyclic [17]. In this case the energy (or momentum) gain is Ae ~ m^a\.…”