Proposed framework for applying squeezed light to multi-photon absorption plasma diagnostics

Journal Article · Mon Jan 26 00:00:00 UTC 2026 · Journal of Instrumentation

DOI: https://doi.org/10.1088/1748-0221/21/01/C01038 · OSTI ID:3021655

Zepp, M.  ^[1]; Beuting, M.  ^[1]; Dangi, M.  ^[1]; Den Hartog, D. J.  ^[1]; Geiger, B.  ^[1]; Kasti, J.  ^[1]; Smith, D. R.  ^[1]; Vishwanath, N.  ^[1]; Choy, J. T.  ^[1]

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1. Univ. of Wisconsin, Madison, WI (United States)

We propose a quantum-enhanced plasma diagnostic based on squeezed states of light. Squeezed light can exhibit super-Poissonian photon statistics, leading to enhanced multiphoton absorption cross-sections compared to classical light. This effect enables improved sensitivity for two-photon excitation of high-energy atomic transitions such as ground-state excitation, and results in increased absorbed power and fluorescence in a plasma. We consider two methods of generating squeezed states and evaluate their advantages and limitations in the context of plasma absorption diagnostics. By comparing with and extending previous theoretical work, we predict an enhancement of the absorption signal by up to seven orders of magnitude at low intensities (10¹ W/m²), with diminishing enhancement persisting up to high intensities (10¹⁰ W/m²). These results suggest that squeezed-light sources offer a viable pathway toward quantum-enhanced plasma diagnostics.

• Research Organization: Univ. of Wisconsin, Madison, WI (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Fusion Energy Sciences (FES)
• Grant/Contract Number: FG02-93ER54222; SC0024471
• OSTI ID: 3021655
• Journal Information: Journal of Instrumentation, Journal Name: Journal of Instrumentation Journal Issue: 01 Vol. 21; ISSN 1748-0221
• Publisher: Institute of Physics (IOP)Copyright Statement
• Country of Publication: United States
• Language: English