Geng Detection Report — "Stable high-power Er:YAG ceramic single-frequency laser at 1645 nm" (Optics Express, 2016)

Academic fraud report · Geng Detector

Summary

Verdict: No fraud indicators detected (cleared). This text-only review of Wang et al. (DOI: 10.1364/OE.24.014966) examined internal numerical consistency, methodological plausibility, equipment/materials timeline, and statistical usage. Key findings: (1) the reported optical efficiency of 52.1% is mathematically consistent with the stated 10.7 W output over 20.5 W pump (10.7/20.5 = 52.195%); (2) the claimed linewidth of 5.75 kHz exactly matches half of the measured self-heterodyne beat bandwidth of 11.50 kHz, consistent with standard delayed self-heterodyne analysis; (3) all equipment (IPG ELR-20, Agilent N9020A MXA, Konoshima Er:YAG ceramic) and techniques (35 km delay fiber) were available by the April 2016 submission date; (4) as a laser-device physics paper, no group-level statistics, p-values, or ANOVA are reported, so p-hacking is not applicable. Limitations: original image files were not available, so pixel-level duplication or splicing (Western blots, micrographs) could not be assessed. Confidence in textual/numerical findings is high; image-based fraud cannot be excluded.

Verdict

Cleared (✅). No fraud indicators were identified within the scope of text-based review. Pixel-level image analysis was not possible due to lack of source figures.

Key findings

Mathematical consistency confirmed: 10.7 W / 20.5 W = 52.195%, matching the claimed 52.1% optical efficiency.
Linewidth consistency confirmed: Self-heterodyne -3 dB beat bandwidth of 11.50 kHz yields a laser linewidth of 11.50 / 2 = 5.75 kHz, exactly matching the reported 5.75 kHz.
Equipment/material timeline plausible: Er:YAG ceramic from Konoshima Chemical Co., Ltd., 1532 nm pump (IPG Photonics ELR-20), Agilent N9020A MXA spectrum analyzer, and 35 km fiber delay (181 μs delay) are all consistent with 2016-era technology.
No statistical anomalies: The paper reports single-device performance metrics (output power, M², linewidth), not group-level statistics; p-hacking is not applicable.
Image-based analysis not possible: Figures 1–7 could not be examined at the pixel level because raw image files were unavailable.

Evidence highlights

Reported max output power: 10.7 W at incident pump power: 20.5 W → efficiency 52.1%.
Reported self-heterodyne beat bandwidth: 11.50 kHz → derived laser linewidth: 5.75 kHz (matches paper).
Submission date: April 2016; pump source, ceramic supplier, and analyzer all existed prior to submission.
DOI: 10.1364/OE.24.014966

Notes

This report covers only textual and numerical dimensions. It does not provide an exclusive conclusion on image reuse, splicing, or other visual manipulation; a PDF-level review of Figs. 1–7 would be required to fully exclude image-based issues.
No contradictions were found between abstract claims, experimental section, and reported numerical results.