Performance Estimation of Hybrid Plasmonic Waveguide in Presence of Stress

In this paper, a detailed numerical investigation has been carried out to find the effect of stress on the optical performances of hybrid plasmonic waveguides (HPWs) operating at 1550 nm wavelength. In the HPWs, the stress is induced due to mismatch in lattice constant and thermal expansion coefficient (TEC) between its different layers. In this paper, optical performances of two HPWs having rectangular and triangular cross-section have been investigated using the finite-element method (FEM) in the presence of stress. For HPW with triangular cross-sections, 25 degrees and 35 degrees ridge angles (alpha) have been chosen categorically, as they are feasible to fabricate. The effect of stress on optical performance parameters, namely effective refractive index, propagation loss, propagation length, and temperature sensitivity for the HPWs, has been investigated. In this study, different metals (Au and Ag) and dielectric materials (SiO(2)and Si3N4) have been introduced in HPWs to realize different magnitude of stresses, which alter the optical performances of the waveguide. Our simulation studies reveal that for all metal and dielectric materials the triangular HPW with 35 degrees ridge angle introduces the highest magnitude of stress as compared to the triangular waveguide with 25 degrees ridge angle and rectangular waveguide. Further, the results show that the presence of stress in the HPW reduces propagation loss and helps in achieving larger propagation length (L-P). The work also shows that the largest magnitude of stress is exerted by the triangular HPW (alpha= 35 degrees) having Si(3)N(4)and Ag materials as dielectric and metal, respectively; and the stress-induced changes in effective index, propagation loss, propagation length and temperature sensitivity of effective index, and propagation length are 0.35%, 42%, 42%, 0.141 x 10(- 4)/degrees C (1.45 x 10(- 4)/degrees C to 1.309 x 10(- 4)/degrees C), and 15.6 nm/degrees C (5.5 nm/degrees C to 21.1 nm/degrees C), respectively. Significant performance variation in HPW in the presence of stress emphasizes the need for the consideration of stress-optic effect while designing HPWs, which can then be employed in photonic integrated circuits.

Automated summary

This study conducts a detailed numerical investigation to explore the impact of stress on the optical performances of hybrid plasmonic waveguides (HPWs) operating at 1550 nm wavelength. It shows that the triangular HPW with a 35-degree ridge angle introduces the highest magnitude of stress, leading to improved optical performances.