Sørensen Simon R, Ulsig Emil Z, Philip Frederik E, Sørensen Frederik R B, Madsen Magnus L, Gardner Asger B, Tønning Peter, Thomsen Simon T, Gravesen Kevin B, Stanton Eric J, Volet Nicolas
Opt Lett. 2024 Aug 1;49(15):4098-4101. doi: 10.1364/OL.529487.
An alternative method for characterizing optical propagation in waveguide structures based on scattered light imaging is presented and demonstrated for the spectral range of 450-980 nm. Propagation losses as low as 1.40 dB/cm are demonstrated in alumina spiral waveguides. AlGaAs-on-insulator waveguides are measured using a tunable laser and compared to cut-back measurements. On AlGaAs, a one-sigma uncertainty of 1.40 and 2.23 dB/cm for TE and TM polarizations is obtained for repetitions of measurements conducted on the same waveguide, highlighting the approach's reproducibility. An open-source toolbox is introduced, allowing for reliable processing of data and estimation of optical propagation losses.
