We study how tunneling through a potential barrier $V\left(x\right)$ can be enhanced by an additional harmonically oscillating electric field $\mathfrak{E}\left(t\right)={\mathfrak{E}}_{0}cos\left(\omega t\right)$ or a similar oscillating force. To this end, we transform into the Kramers-Henneberger frame and calculate the coupled Floquet channels numerically. We find distinct signatures of resonances when the incident energy $E$ equals the driving frequency $\omega =E$, which clearly shows the breakdown of the time-averaged potential approximation in this regime. As a simple model for experimental applications (e.g., in solid-state physics), we study the rectangular potential, which can also be benchmarked with respect to analytical results. Finally, we consider the truncated Coulomb potential relevant for nuclear fusion.

• Received 13 October 2023
• Revised 31 January 2024
• Accepted 12 March 2024

DOI:https://doi.org/10.1103/PhysRevResearch.6.023056

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

Published by the American Physical Society