Multi-photon stimulated grasers assisted by laser-plasma interactions

TL;DR

This paper proposes a theoretical method for gamma-ray amplification using multi-photon stimulated emission facilitated by high-intensity laser-plasma interactions, potentially overcoming previous limitations in gamma-ray laser development.

Contribution

It introduces a novel multi-photon mechanism for gamma-ray amplification that leverages high-power laser systems and tunable photon bandwidths, expanding the possibilities for gamma-ray laser applications.

Findings

Multi-photon stimulated emission can have a larger cross-section than one-photon processes.

Tunable photon bandwidths can reduce linewidth broadening.

The scheme can be applied to non-Mossbauer nuclei with appropriate photon energy tuning.

Abstract

We investigate theoretically the possibility of achieving the stimulated amplification of $\gamma$-rays. Herein, our approach circumvents the so-called ``graser dilemma" through a non-linear, multi-photon mechanism. Our work foresees the combination of a high-intensity $\gamma-$flash generated by the interaction of a high-intensity laser pulse with plasma and intensive photons supplied by an additional laser. We show that multi-photon stimulated emission processes can have a larger effective cross-section compared to a one-photon process. The bandwidth of the supplied photons can also be tuned to curtail linewidth broadening. Naturally, Mossbauer transitions can be chosen to apply the scheme in the first instance. Furthermore, we derive that even multi-photon stimulated emission in the form of an anti-Stokes type could allow our scheme to be applied to non-Mossbauer nuclei, provided that the supplied photon energy can be tuned to compensate for the recoil and other broadening induced losses. The graser development can be spearheaded using multi-PW class high-power laser systems such as the 10 PW installation at Extreme Light Infrastructure - Nuclear Physics (ELI-NP) in Romania.