Extremely high-intensity laser interactions with fundamental quantum systems

Abstract: The field of laser-matter interaction traditionally deals with the response of atoms, molecules and plasmas to an external light wave. However, the recent sustained technological progress is opening up the possibility of employing intense laser radiation to trigger or substantially influence physical processes beyond atomic-physics energy scales. Available optical laser intensities exceeding $10^{22}\;\text{W/cm$^2$}$ can push the fundamental light-electron interaction to the extreme limit where radiation-reaction effects dominate the electron dynamics, can shed light on the structure of the quantum vacuum, and can trigger the creation of particles like electrons, muons and pions and their corresponding antiparticles. Also, novel sources of intense coherent high-energy photons and laser-based particle colliders can pave the way to nuclear quantum optics and may even allow for potential discovery of new particles beyond the Standard Model. These are the main topics of the present article, which is devoted to a review of recent investigations on high-energy processes within the realm of relativistic quantum dynamics, quantum electrodynamics, nuclear and particle physics, occurring in extremely intense laser fields.

• The paper demonstrates that ultra-intense lasers (exceeding 10^22 W/cm^2) trigger key QED phenomena such as multiphoton Compton scattering and vacuum polarization.
• It employs advances in laser technology, including setups like ELI and HiPER, to investigate radiation reaction effects and cascading processes in charged particles.
• The study highlights potential applications in nuclear quantum optics and high-energy physics, offering new avenues for probing fundamental particle interactions.

Overview of High-Intensity Laser Interactions with Quantum Systems

Introduction

The paper on "Extremely high-intensity laser interactions with fundamental quantum systems" investigates the dynamics at play when intense laser radiation interacts with fundamental quantum structures such as electrons, muons, and nuclei, revealing its potential in probing quantum vacuum properties and triggering high-energy particle phenomena.

High-Intensity Laser Technology

Recent advancements in laser technology have paved the way to explore interactions far beyond atomic scales. Current laser systems, achieving intensities greater than $10^{22} \, \text{W/cm}^2$, facilitate experiments at the intersection of ultra-relativistic quantum electrodynamics (QED) and particle physics. Upcoming facilities like ELI and HiPER promise to enhance these capabilities, aiming at calibrating laser fields to enable novel radiation sources for high-energy physics investigations.

Quantum Electrodynamics and Relativistic Dynamics

Relativistic QED phenomena become observable as laser intensities surpass $10^{22} \, \text{W/cm}^2$, reaching potential in processes such as multiphoton Compton scattering, electron-positron pair production, and the exploration of QED cascading. The discussion distinguishes classical from quantum regimes through parameters such as the classical nonlinearity parameter $\xi$ and the quantum parameter $\chi$, governing photon recoil and radiation reaction effects.

Vacuum-Polarization Effects

The paper explores vacuum-polarization effects as a profound prediction of QED, depicting how high-intensity fields could manifest interactions between photons via virtual electron-positron pairs. Such interactions are crucial for experiments designed to observe photon-photon scattering in vacuum, a challenge due to the high photon energy thresholds needed to detect tangible effects.

Particle Production Processes

The scope of particle production dynamics extends to interactions where photons merge in high-energy fields, alongside processes where Coulomb and laser fields intersect to produce muon-antimuon and pion-antipion pairs. Experiments utilizing the LHC's proton beams coupled with high-intensity lasers demonstrate these high-order processes, providing a unique environment to study beyond-Standard-Model physics.

Radiation Reaction and QED Cascades

The radiation-reaction effect, a significant force altering charged particle dynamics in intense fields, is scrutinized both classically, via the Landau-Lifshitz equation, and quantum mechanically. This field also explores QED cascades, specifically how electron, positron, and photon populations evolve under intense fields, eventually limiting achievable intensities in laser-plasma interactions.

Nuclear Interactions and Prospects

Future directions include leveraging high-frequency laser systems to probe nuclear processes directly, facilitating novel experiments in nuclear quantum optics and extending to applications like nuclear batteries through isomeric transitions.

Conclusion

This comprehensive examination of extremely high-intensity laser interactions illustrates the vast potential of laser-driven experiments in advancing quantum, particle, and nuclear physics. As these technologies evolve, they promise not only to deepen our understanding of fundamental particle dynamics but also to unlock practical applications in medicine and energy, revolutionizing fields with intense photonic tools capable of modifying quantum and nuclear states at unprecedented scales. Future experimental setups promise to harness these capabilities, potentially pushing the frontiers of quantum dynamics and particle physics into new domains.