Exotic atoms in superintense laser fields

Abstract

Abstract. The interaction of very strong laser fields with hydrogenlike atomic systems is analyzed theoretically. It is shown that the usual magnetic field-induced limitations for efficient recollisions can be overcome by employing exotic atoms rather than ordinary ones. In this way not only high-harmonic radiation in the MeV regime could be produced, but also laser-induced nuclear effects and particle reactions come into the reach of near-future laser facilities.

High harmonic interferometry of the Lorentz force in strong mid-infrared laser fields

“…However, this programme runs into a surprising limitation in that the dipole approximation breaks down in the long wavelength regime: as the wavelength increases, the electron has progressively longer times to accelerate in the field, and the magnetic Lorentz force =F v B m becomes significant [7]. This pushes the electron along the laser propagation direction and, when strong enough, makes the electron wavepacket completely miss its parent ion, quenching all recollision phenomena, including in particular high harmonic generation [8][9][10][11][12][13][14][15].Multiple schemes have been proposed to overcome this limitation, both on the side of the medium, from antisymmetric molecular orbitals [16] through relativistic beams of highly charged ions [17] to exotic matter like positronium [18] or muonic atoms [19] , and on the side of the driving fields, including counter-propagating mid-IR beams [20,21], the use of auxiliary fields propagating in orthogonal directions [22], fine tailoring of the driving pulses [23], counter-propagating trains of attosecond pulses [24] in the presence of strong magnetic fields [25], and collinear and non-collinear x-ray initiated HHG [26,27].…”

“…Multiple schemes have been proposed to overcome this limitation, both on the side of the medium, from antisymmetric molecular orbitals [16] through relativistic beams of highly-charged ions [17] to exotic matter like positronium [18] or muonic atoms [19], and on the side of the driving fields, including counter-propagating mid-IR beams [20,21], the use of auxiliary fields propagating in orthogonal directions [22], fine tailoring of the driving pulses [23], counter-propagating trains of attosecond pulses [24] in the presence of strong magnetic fields [25], and collinear and non-collinear x-ray initiated HHG [26,27], though in general these methods tend to be challenging to implement. Perhaps most promisingly, one can also use the slight ellipticity in the propagation direction present in very tightly focused laser beams [28,29] and in waveguide geometries.…”