Optimized silicon nitride-spaced graphene electro-optic modulator with high efficiency and bandwidth
- Optical modulators with high modulation efficiency, large operational bandwidth, high-speed and low energy consumption is essential for the advancement of on-chip optical signal processing. To overcome the bandwidth-efficiency trade-off in graphene optical modulators, a buried silicon nitride waveguide-coupled double-layer graphene electro-absorption (EA) optical modulator has been proposed. In the proposed design, silicon nitride layer is also embedded between the two graphene layers as a dielectric spacer to enhance the graphene-light interaction. An extensive simulation has been performed to optimize the dielectric spacing layers between the two graphene for optimal device performance including the waveguide dimensions and optical modes profile. The simulated results show a high modulation efficiency of 1.1 dB/V and a modulation depth of 0.16 dB/µm, corresponding to a 15-dB extinction ratio for a 100 µm device at 1550 nm, with a 30 nm spacer and 12 V driving voltage. The proposed modulator achieves a 14 GHz bandwidth and operates over a 1050 nm broadband operation spectral range. The concurrent presence of high modulation bandwidth and efficiency renders these modulator designs highly viable for on-chip optical communication applications.
| URN: | urn:nbn:de:kobv:526-opus4-20597 |
|---|---|
| Publisher DOI: | https://doi.org/10.1007/s11082-025-08310-0 |
| Author: | Ashraful Islam RajuORCiD, Pawan Kumar Dubey, Rasuole LukoseORCiD, Christian WengerORCiD, Andreas MaiORCiD, Mindaugas Lukosius |
| Parent Title (English): | Optical and Quantum Electronics |
| Document Type: | Article |
| Language: | English |
| Year of Publication: | 2025 |
| Volume: | 57 |
| Issue: | 7 |
| Article Number: | 402 |
| Publisher: | Springer Nature |
| Faculties an central facilities: | Fachbereich Ingenieur- und Naturwissenschaften |
| Publishing Institution: | Technische Hochschule Wildau |
| Tag: | electro-optical modulator; graphene modulator; modulation efficiency; silicon nitride waveguide |
| Source: | Raju, A.I., Dubey, P.K., Lukose, R. et al. Optimized silicon nitride-spaced graphene electro-optic modulator with high efficiency and bandwidth. Opt Quant Electron 57, 402 (2025). https://doi.org/10.1007/s11082-025-08310-0 |
| Dewey Decimal Classification: | 6 Technik, Medizin, angewandte Wissenschaften / 62 Ingenieurwissenschaften / 621 Angewandte Physik |
| Licence (German): | Creative Commons - CC BY-NC-ND - Namensnennung - Nicht kommerziell - Keine Bearbeitungen 4.0 International |
| Release Date: | 2025/12/01 |



