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arXiv · 2102.07474

Dynamically assisted tunneling in the impulse regime

Christian Kohlfürst·Friedemann Queisser·Ralf Schützhold
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Abstract

We study the enhancement of tunneling through a potential barrier $V(x)$ by a time-dependent electric field with special emphasis on pulse-shaped vector potentials such as $A_x(t)=A_0/\cosh^2(\omega t)$. In addition to the known effects of pre-acceleration and potential deformation already present in the adiabatic regime, as well as energy mixing in analogy to the Franz-Keldysh effect in the non-adiabatic (impulse) regime, the pulse $A_x(t)$ can enhance tunneling by ``pushing'' part of the wave-function out of the rear end of the barrier. Besides the natural applications in condensed matter and atomic physics, these findings could be relevant for nuclear fusion, where pulses $A_x(t)$ with $\omega=1~\rm keV$ and peak field strengths of $10^{16}~\rm V/m$ might enhance tunneling rates significantly.

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Christian Kohlfürst, Friedemann Queisser, Ralf Schützhold. 2021-02-15. Dynamically assisted tunneling in the impulse regime. https://doi.org/10.1103/physrevresearch.3.033153

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