Soft photon approximation in a laser field: applications
Abstract
We apply the soft photon approximation to QED processes in a strong plane-wave laser field. New compact expressions for the emission factors are presented, which simplify the generalization to multiple soft photon emission. The method is applied to nonlinear single, double, and N-photon Compton scattering. For single Compton scattering, we show that the soft photon approximation reproduces the exact spectrum with accuracy 𝒪(ω/ε), significantly outperforming the classical radiation theory. For double Compton scattering, we derive analytical expressions for the differential probability in two kinematic regimes: when both photons are soft, and when one photon is soft while the other has arbitrary energy. We present a compact analytical expression for the amplitude of N-photon emission within the soft photon approximation. A numerical implementation in Wolfram Mathematica for single and double Compton scattering is provided.
Versions
Related
- Anomalous soft photon production can be understood as photon emission during hadronisation
- Soft-photon theorem near static spherical horizons in generic dimensions
- Machine learning for the design and prediction of soft-magnetic electromagnetic shielding FeCo-based alloys in laser cladding
- Windowed Catodyne Measurements: Continuum Approximation versus Exact Discrete Photon-Number Treatment
- Single-Shot Fidelity Reveals Hard and Soft Limits: A Universal Yardstick for Photon-Number-Resolving Detectors
BibTeX
@misc{krachkov2026soft,
title = {{Soft photon approximation in a laser field: applications}},
author = {Peter A. Krachkov and Simon V. Sorokin},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2607.11160},
eprint = {2607.11160},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2607.11160},
}
RIS
TY - UNPB
TI - Soft photon approximation in a laser field: applications
AU - Peter A. Krachkov
AU - Simon V. Sorokin
PY - 2026
DA - 2026/09/09
PB - arXiv
DO - 10.48550/arxiv.2607.11160
UR - https://arxiv.org/abs/2607.11160
AB - We apply the soft photon approximation to QED processes in a strong plane-wave laser field. New compact expressions for the emission factors are presented, which simplify the generalization to multiple soft photon emission. The method is applied to nonlinear single, double, and N-photon Compton scattering. For single Compton scattering, we show that the soft photon approximation reproduces the exact spectrum with accuracy 𝒪(ω/ε), significantly outperforming the classical radiation theory. For double Compton scattering, we derive analytical expressions for the differential probability in two kinematic regimes: when both photons are soft, and when one photon is soft while the other has arbitrary energy. We present a compact analytical expression for the amplitude of N-photon emission within the soft photon approximation. A numerical implementation in Wolfram Mathematica for single and double Compton scattering is provided.
ER -