English

Theoretical framework for real time sub-micron depth monitoring using quantum inline coherent imaging

Instrumentation and Detectors 2023-09-19 v1 Quantum Physics

Abstract

Inline Coherent Imaging (ICI) is a reliable method for real-time monitoring of various laser processes, including keyhole welding, additive manufacturing, and micromachining. However, the axial resolution is limited to greater than 2 {\mu}m making ICI unsuitable for monitoring submicron processes. Advancements in Quantum Optical Coherence Tomography (QOCT), which uses a Hong-Ou-Mandel (HOM) interferometer, has the potential to address this issue by achieving better than 1 {\mu}m depth resolution. While time-resolved QOCT is slow, Fourier domain QOCT (FD-QOCT) overcomes this limitation, enabling submicron scale real-time process monitoring. Here we review the fundamentals of FD-QOCT and QOCT and propose a Quantum Inline Coherent Imaging system based on FD-QOCT. Using frequency entangled sources available today the system has a theoretical resolution of 0.17 microns, making it suitable for submicron real-time process monitoring.

Keywords

Cite

@article{arxiv.2309.09325,
  title  = {Theoretical framework for real time sub-micron depth monitoring using quantum inline coherent imaging},
  author = {Alexander Wainwright and Khaled Madhoun},
  journal= {arXiv preprint arXiv:2309.09325},
  year   = {2023}
}

Comments

12 pages, 8 figures

R2 v1 2026-06-28T12:24:05.281Z