20.500.12556/RUL-182960 Multi wavelength measuring of the gold nanoparticles by the optical fiber interferometer An optical fiber-based Mach–Zehnder interferometer was developed for photothermal detection of gold nanoparticles in aqueous suspensions. The excitation laser locally heats the suspension, inducing a refractive index change that is detected as a phase shift in the interferometer's measuring arm. By employing excitation wavelengths of 450 nm and 525 nm, the wavelength-dependent absorption was analyzed and compared to Mie theory predictions, enabling simultaneous determination of particle size and concentration. The absorption cross-section ratio, calculated from measurements at both wavelengths, depends only on particle size and provides the basis for size determination without prior knowledge of concentration. The system demonstrated high sensitivity, with detection limits as low as 8 × 10⁶ particles per milliliter for 100 nm gold nanoparticles. The optical fiber-based architecture offers simplicity, robustness, and potential for integration into portable sensing systems for nanoparticle characterization and biosensing applications. optical fiber interferometer photothermal detection gold nanoparticles vlakenski interferometer fototermalna detekcija zlati nanodelci true false true Angleški jezik Slovenski jezik Bibliografija 2026-05-29 13:02:10 2026-05-29 13:02:18 2026-05-30 04:58:38 0000-00-00 00:00:00 2026 0 0 7 str. art. 118046 Vol. 408 2026 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 620.3 1873-3069 10.1016/j.sna.2026.118046 279851267 RAZ_Agrez_Vid_2026.pdf RAZ_Agrez_Vid_2026.pdf 1 291179A97FDE6E9BD62318B466C2CBD2 91a45fcb0dd0d61710eb4cb87a2d1a2926d3d829ffa259c566ff4462dfc95b7a ab7080f1-5b4f-11f1-b0ab-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=234673 https://www.sciencedirect.com/science/article/pii/S0924424726005972?via%3Dihub 1 8468f03a-5b4d-11f1-b0ab-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=234672 Fakulteta za strojništvo 0 0 0