We propose a multiple-slot silica high-mesa waveguide for infrared sensing considering the possibility of realizing a higher portion of an optical field out of the waveguide (which is defined as “Γair”). Low Γair leads to less light power being used for sensing, which limits sensing capabilities. The simulated results showed a high Γair of 20.3% for a quadruple structure under λ = 1550 nm. A scattering loss of 0.06 dB/cm was predicted theoretically as well.
