The 30th International Conference on Advanced Laser Technologies LD-P-1
ALT'23
Influence of the input field of an array waveguide grating multiplexer
on its spectrum
I.V. Babichek1'2, A.A. Sapegin2, E.S. Shamin123, V.V. Svetikov3 4
1MIPT (NRU), Moscow, Russia
2 JSC «MERI», Zelenograd, Russia
3 JCS «ZNTC», Zelenograd, Russia
4 Prokhorov General Physics Institute of the Russian Academy of Sciences
Babichek. iv@phystech. edu
One of the key elements of integrated photonics, the optical (de)multiplexer, divides the signal along the wavelength or combines multiple signals with different wavelengths into a single signal. This device is widely used for optical communication and as an integral spectrometer. The arrayed waveguide grating (AWG) design is of a particular interest, because it has a good balance between the free spectral range and resolution. But further channel densification is problematic because lasers' instability starts to be noticeable within the spectral width of one channel [1], other spectrum shifting effects and error in wavelength matching. This is corrected by using the multiplexer's transmission characteristic's known as the flat-top peak shape. One approach of getting such a form in AWG is by adding MMIs (tapers) to input and/or output waveguides, which convert single mode input to multimode output and widen the amplitude profile. The width of input field determines one of the most important spectral characteristics of an AWG — the 3 dB bandwidth. In this study the influence of the input field on the AWG spectrum is analyzed. Existing taper design techniques [2,3] are reviewed and the impact of the taper parameters on the input field is discussed.
[1] E. Wildermuth, Performance optimization of flat-top passband arrayed waveguide grating demultiplexers. Diss. ETH Zurich, (2000).
[2] D. Dai, W. Mei, S. He, Using a tapered MMI to flatten the passband of an AWG, Optics Communications, 219(1-6), 233-239, (2003).
[3] Y. Fu et al., Efficient adiabatic silicon-on-insulator waveguide taper, Photonics Research, 2(3), A41-A44, (2014).