High Performance 7 \times 8 Ge-on-Si Arrayed Waveguide Gratings for the Midinfrared

• Published in: IEEE journal of selected topics in quantum electronics Vol. 24; no. 6; pp. 1 - 8
• Main Authors: Malik, Aditya, Stanton, Eric J., Junqian Liu, Spott, Alexander, Bowers, John E.
• Format: Journal Article
• Language: English
• Published: IEEE 01-11-2018
• Subjects: Arrayed waveguide gratings; Couplings; Fabrication; midinfrared; planar waveguides; Propagation losses; Quantum cascade lasers; Silicon; Waveguide lasers
• ISSN: 1077-260X; 1558-4542
• DOI: 10.1109/JSTQE.2018.2819889

Ge-on-Si low-loss waveguides and 7 × 8 arrayed waveguide gratings (AWGs) are presented for operation near 4.7 μm wavelength. Propagation loss in the range of 3 dB/cm for fully etched waveguides and 1 dB/cm for shallow-etched waveguides is reported. 200 GHz AWGs in a 7 × 8 configuration with various waveguide aperture widths and etch depths are designed and characterized. For fully etched AWGs, the insertion loss values as low as -2.34 and 3 dB mean cross talk of -29.63 dB are achieved. The shallow-etched AWG has an insertion loss of -1.52 dB and crosstalk of -28 dB.