English

Phase-Programmable Free Electron Quantum States in Synthetic Momentum Space

Quantum Physics 2026-07-08 v1

Abstract

Light-electron interactions generate synthetic momentum-space dynamics that can be used to engineer free electron quantum states. Here we develop coherent control protocols in which the optical phase acts as the controllable hopping phase of a Floquet-Bloch momentum lattice. Pontryagin optimization designs phase-only waveforms that prepare selected momentum populations and coherent few-sideband superpositions with programmable relative phases. In a complementary Bragg regime protocol, dynamical phase matching selectively couples neighboring sidebands and enables deterministic sequential state synthesis. Full wave-packet simulations based on the minimal-coupling Hamiltonian identify the tolerance window set by phase noise, detuning, and finite momentum spread. The two protocols expose a speed-selectivity tradeoff between ultrafast multilevel interference control and slower resonant engineering, establishing programmable free electron sidebands as a platform for ultrafast quantum state synthesis.

Cite

@article{arxiv.2607.07445,
  title  = {Phase-Programmable Free Electron Quantum States in Synthetic Momentum Space},
  author = {Alatz Alvarez-Ahedo and Miriam Lazo and Tian-Niu Xu and Yiming Pan and Mikel Sanz and Yongcheng Ding},
  journal= {arXiv preprint arXiv:2607.07445},
  year   = {2026}
}

Comments

13 pages, 6 figures

R2 v1 2026-07-22T20:31:46.862Z