Dynamically assisted Sauter-Schwinger effect in inhomogeneous electric fields

Abstract

Via the world-line instanton method, we study electron-positron pair creation by a strong (but sub-critical) electric field of the profile E/ cosh 2 (kx) superimposed by a weaker pulse E / cosh 2 (ωt). If the temporal Keldysh parameter γ ω = mω/(qE) exceeds a threshold value γ crit ω which depends on the spatial Keldysh parameter γ k = mk/(qE), we find a drastic enhancement of the pair creation probability -reporting on what we believe to be the first analytic non-perturbative result for the interplay between temporal and spatial field dependences E(t, x) in the Sauter-Schwinger effect. Finally, we speculate whether an analogous effect (drastic enhancement of tunneling probability) could occur in other scenarios such as stimulated nuclear decay, for example.

Reducible contributions to quantum electrodynamics in external fields

“…Related results now exist for the effective action at two-and three loops [14,15] in a constant background, (anti-)self-dual backgrounds [16][17][18] and at one-loop order for various non-constant backgrounds such as Sauter pulses [19][20][21] and a pulsed Hermite and Laguerre-Gaussian laser beam [22]. See also [23] for the full mass range analysis of the QED effective action for a nontrivial background with some special symmetry.…”

“…This effect has recently received renewed attention [5][6][7][8][9] due to the prospects of investigating pair creation using future laser facilities. For the status of current and future laser facilities, making study of these backgrounds of great experimental interest for the coming years see, for example, the information at [10-13]).Related results now exist for the effective action at two-and three loops [14,15] in a constant background, (anti-)self-dual backgrounds [16][17][18] and at one-loop order for various non-constant backgrounds such as Sauter pulses [19][20][21] and a pulsed Hermite and Laguerre-Gaussian laser beam [22]. See also [23] for the full mass range analysis of the QED effective action for a nontrivial background with some special symmetry.…”

Dynamically assisted Schwinger effect beyond the spatially-uniform-field approximation

“…Finally, we stress that the spatial dependence of the external background in the context of Schwinger pair production was considered so far in a very few studies [16,17,20,[26][27][28]. We expect that multidimensional inhomogeneities should be significant for a much broader class of possible scenarios.…”

Dynamically assisted nuclear fusion

“…with the static potential barrier V (r) while the timedependent XFEL field is represented by A z (t), cf. [23]. As the next step (see also [16,[24][25][26]), we split the eikonal function S(t, r) = S 0 (t, r) + S 1 (t, r) into the zeroth-order solution S 0 (t, r) of the static tunneling problem…”