Unlimited Energy Gain in the Laser-Driven Radiation Pressure Dominant Acceleration of Ions

TL;DR

This paper demonstrates that by exploiting transverse expansion and phase-locking in radiation pressure acceleration, ions can achieve unlimited energy gain, offering a new method to significantly enhance laser-driven ion energies.

Contribution

It introduces a novel mechanism combining transverse expansion and optimal laser shaping to enable unlimited ion energy gain in radiation pressure acceleration.

Findings

Transverse expansion reduces ion density, increasing energy and velocity.

Phase-locking with the electromagnetic wave leads to unlimited ion energy gain.

Optimal laser pulse shaping enhances the acceleration process.

Abstract

The energy of the ions accelerated by an intense electromagnetic wave in the radiation pressure dominated regime can be greatly enhanced due to a transverse expansion of a thin target. The expansion decreases the number of accelerated ions in the irradiated region increasing the energy and the longitudinal velocity of remaining ions. In the relativistic limit, the ions become phase-locked with respect to the electromagnetic wave resulting in the unlimited ion energy gain. This effect and the use of optimal laser pulse shape provide a new approach for great enhancing the energy of laser accelerated ions.