I Simposio de Postgrado 2023. Ingeniería, ciencias e innovación

MÓDULO_ 01 Astronomía y Física 42 ULTRA-LOW-LOSS BROADBAND MULTIPORT OPTICAL SPLITTERS Paloma Vildoso 1,2 *, Rodrigo A. Vicencio 1,2 , Jovana Petrovic 2 1 Departamento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile. 2 Millenium Institute for Research of Optics-MIRO *Email: paloma.vildoso@ug.uchile.cl ABSTRACT Conventional design of Multiport coupler (or Splitter) relies on concatenation of directional couplers or multimode interfer- ence [1-4]. However, they show a considerable insertion loss, which limits their bandwidth and footprint requirements to circuits application. Recently, nanotechnology has tabled direct inverse design of these devices by electron-beam lithography, demonstrating that they can fulfill all above requirements [5-6] but having a high cost of time and energy to design a single spe- cific Splitter. In this work we present an efficient inverse design algorithm and experimental implementation of Multiport cou- plers with low insertion loss, broad bandwidth, small footprint, arbitrary splitting ratio and low time-energy cost, showing themselves to be competitive compared to the current design. To demonstrate the capabilities of our method, we design sev- eral splitting ratios 1 N based on single mode linearly coupled waveguide arrays (WGAs) and fabricate in a borosilicate waffer by femtosecond laser writing technique [7]. Splitters shows near zero insertion loss and bandwidth of 20 60 nm while maintain- ing low imbalance < 0.5 dB. We demonstrate that one Multiport can be tuned to achieve different splitting ratios. Furthermore, the scaling of the splitter footprint follows an exponential rela- tion in glass. Finally, we offer new possibilities for multiple ap- plications such as quantum optics, logical operations, sensing and communications. REFERENCES [1] A. Politi,M. J. Cryan, J. G. Rarity, S. Yu, and J. L. O’Brien, “Silica-on-siliconwaveguide quantumcircuits,” Science 320, 646–649 (2008). [2] Wang, J., Paesani, S., Ding, Y., Santagati, R., Skrzypczyk, P., Salavrakos, A.,Thompson,M.G. . “Multidimensional quantum entanglementwith large-scale integrated optics.” Science, 360(63 86), 285–291. (2018) [3] C.Huang, D.Wang,W.Zhang,B.Wang,A.N.Ta it ,T.F.de Lima,B.J.Shastri,andP.R.Prucnal, “High-capacityspace-division multi-plexingcommunicationswithsiliconphotonicblindsourceseparation,” J.Light-waveTechnol.40,1617–1632 (2022). [4] Cariñe, J., Asan-Srain, M. N., Lima, G., & Walborn, S. P, “Maximizing quantum discord from interference in multi-port fiber beamsplitters” . Npj Quantum Information, 7(1),(2021) [5] H.Xie,Y.Liu,W.Sun,Y.Wang,K.Xu, J.Du,Z.He, andQ.Song, “Inverselydesigned1x4powersplitterwitharbitraryratios at2µmspectralband,” IEEEPhotonics Journal 10,1–6 (2018). [6] Tahersima, M.H., Kojima, K., Koike-Akino, T. et al. “Deep Neural Network Inverse Design of Integrated Photonic Power Splitters.” Sci Rep 9, 1368 (2019). [7] Szameit, A., & Nolte, S. ”Discrete optics in femtosecond-láser-written photonic structures” . J. Phys. B: At. Mol. Opt. Phys. 43,163001.(2010) Figura 1: (a) Splitter Design. (b) Femtosecond laser writing technique. (c1) and (c2) White light microscopy and intensity output of five-ports Splitter, respectively. (d) Experimental results (Top) and Simulation (Bottom) of waveguide intensities versus z of 1 × 5 Splitter. Black dashes line shows equal splitting. (e) Multifunctionality demonstration of Multiport coupler. FISICAYASTROFÍSICA Ultra-low-loss broadband multiport optical Splitters Paloma Vildoso 1,2* , Rodrigo A. Vicencio 1 , 2 , Jovana Petrovic 3 amento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile. 2 Millenium Institute for Research of Optcis-MIRO 2 Millenium Institute for Research of Optcis-MIRO *paloma.vildoso@ug.uchile.cl nal design of Multiport coupler (or Splitter) relies on con catenation of direction l or multimode interference [1-4]. However, they show a considerable insertion loss, mits their bandwidth and footprint requirements to circuits application. Recently, ology has tabled direct inverse design of these devices by electron-beam lithography, ting that they can fulfill all above requirements [5-6] but having a high cost of time y to design a single specific Splitter. In this work we present an efficient inverse orithm and experimental implementation of Multiport cou- plers with low insertion d bandwidth, small footprint, arbitrary splitting ratio and low time-energy cost, hemselves to be competitive compared to the current design. To demonstrate the s of our method, we design several splitting ratios 1 N based on single mod linearly aveguide arrays (WGAs) and fabricate in a borosilicate waffer by femtosecond laser chnique [7]. Splitt rs shows nea zero insert o loss and bandwidth of 20 60 nm while ng low imbala ce < 0 . 5 dB. We d monstrate that one Multiport can be tuned to fferent splitting ratios. Fur hermore, he scaling of the splitter footprint follows an al relation in glass. F nally, we offer new possibilities fo m ltiple applications such as ptics,logical operations, sensing and communications. 1 (a) Splitter Design. (b) Femtosecond laser writing technique. (c1) and (c2) White light roscopy and intensity outputof five-ports Splitter, respectively. (d) Experimental results Top) and Simulation (Bottom) of waveguide intensities versus z of1 × 5 Splitter. Black es line shows equal splitting. (e) Multifunctionality demonstration of Multiport coupler.