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arXiv · 2610.17166

Programmable Hard-X-Ray Spectral Comb Generation via Laser-Compton Scattering

Hao Zhang·1Ji Qiang·Shukui Zhang·Sergio Carbajo
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Abstract

Independent control of line spacing and offset underpins programmable frequency-comb spectroscopy, yet it has not been established for hard-X-ray sources based on inverse Compton scattering after electron transport and angular collection. Self-consistent multi-particle tracking and Li'enard-Wiechert radiation calculations model a transported 10 pC beam and its angle-integrated spectrum near 11 keV. Laser pulse separation programs the comb spacing, while pulse-to-pulse phase translates the entire line grid at fixed spacing. The spacing model agrees within 0.52%, while transport and optics change the phase-transfer slope by less than 0.2%. At fixed electron spot size, the largest resolvable separation scales as the inverse square of normalized emittance; subnanometer bunches also produce a mode-locked train with 13.9 as spacing. This two-coordinate programmability enables phase-stepped multicolor measurements and offers routes to hard-X-ray Ramsey interferometry, coherent control of core and nuclear excitations, and attosecond nonlinear spectroscopy.

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Hao Zhang, 1Ji Qiang, Shukui Zhang, Sergio Carbajo. 2026-10-12. Programmable Hard-X-Ray Spectral Comb Generation via Laser-Compton Scattering. https://arxiv.org/abs/2610.17166

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