Narrow-core hollow optical waveguide with nanostructured SOI as ultra-low loss platform for efficient photodetection
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A nanostructured hollow optical waveguide based on high-index contrast grating (HCG) embedded SOI is proposed. An ultra-low propagation loss of 1.22 dB/m even at narrow, 1-\(\upmu \)m thick, air-core is reported. A high-performance photodetection is realized by the introduction of hollow core in form of intrinsic region in the photodetection (PIN) layer within HCG-assisted narrow-core waveguide. A sufficiently high responsivity of 0.8 A/W and quantum efficiency of 64% are obtained at 1550-nm which is possible because of the presence of surface modes within HCG which get coupled in the photodetection layer leading to a strong optical confinement in that layer. High reflectivity, small penetration length and coupling of lateral surface modes in HCG make it possible to offer improved waveguiding and hence photodetection.
KeywordsGratings Photonic crystal waveguide Silicon Optical detectors
- 6.Kaur, J., Kumar, M., Kaushik, B.K.: Electrical tuning of optical delay in graphene-based photonic crystal waveguide. IEEE J. Quantum Elecron. 51, 1–5 (2015)Google Scholar
- 11.Ahn, D., Kimerling, L.C., Michel, J.: Efficient evanescent wave coupling conditions for waveguide-integrated thin-film Si/Gephotodetectors on silicon-on-insulator/germanium-on-insulator substrates. J. Appl. Phys. 110, 083115-1–083115-9 (2011)Google Scholar
- 21.Kumar, M., Sakagichi, T., Koyama, F.: Giant birefringence and tunable differential group delay in Bragg reflector based on tapered three-dimensional hollow waveguide. Appl. Phys. Lett. 94, 061112-1–061112-3 (2009)Google Scholar