Field canalization using anisotropic 2D plasmonics

Optical devices capable of suppressing diffraction nature of light are of great technological importance to many nanophotonic applications. One important technique to achieve diffractionless optics is to exploit field canalization effect. However, current technological platforms based on metamaterial structures typically suffer from strict loss-confinement trade-off, or lack dynamic reconfigurability over device operations. Here we report an integrated canalization platform that can alleviate this performance trade-off. It is found that by leveraging material absorption of anisotropic 2D materials, the dispersion of this class of materials can flatten without increasing propagation losses and compromising confinement. The realization of such plasmon canalization can be considered using black phosphorus (BP), where topological transition from elliptic to hyperbolic curves can be induced by dynamically leveraging material absorption of BP. At the transition point, BP film can support long range, deeply subwavelength, near-diffractionless field propagation, exhibiting diffraction angle of 5.5°, propagation distance of 10λspp, and λspp < λ0/300.

Diode-Pumped Fluorescence in Visible Range From Femtosecond Laser Inscribed Pr:LuAG Waveguides

Trivalent praseodymium (Pr3+) is the most established rare-earth ion for the direct generation of visible light. In our work, based on Pr-doped Lu3Al5O12 (LuAG) single crystal, cladding waveguides are fabricated by applying femtosecond laser inscription with different parameters. The main characteristics of the waveguides such as mode distributions, propagation losses are investigated. The investigations on confocal micro-photoluminescence enable us to illustrate femtosecond laser induced modifications in Pr:LuAG matrix. The waveguides are further pumped at a wavelength of 450 nm with an InGaN laser diode. Guided fluorescence emissions in visible range covering green, yellow-green, orange and red are obtained with a maximum slope efficiency of 4 × 10−4.

Optical Nanocomposites Containing Low Refractive Index MgF2 Nanoparticles

Nanoparticles composed of magnesium fluoride were successfully introduced into polymer matrices used for the fabrication of planar optical waveguides. Optical layers without visible scattering were successfully prepared. The transparent nanocomposites were formulated by direct mixing of modified MgF2 nanoparticles with fluorinated co-polymer matrix or acrylate monomer mixture with a help of additional solvent. An addition of MgF2 nanoparticles results in decrease of refractive index and thermo-optic coefficient of the polymer but increases substantially the optical propagation losses for planar waveguide at 1547 nm.

High-Order Analytical Formulation of Soliton Self-Frequency Shift

<div>We derive an analytical formulation of the Raman-induced frequency shift experienced by a fundamental soliton. By including propagation losses, self-steepening, and dispersion slope, the resulting formulation is a high-order (HO) extension of the well-known Gordon's formula for soliton self-frequency shift (SSFS). The HO-SSFS formula closely agrees with numerical results of the generalized nonlinear Schrödinger equation, but without the computational complexity and required computation time. The HO-SSFS formula is a useful tool for the design and validation of wavelength conversion systems and supercontinuum generation systems.</div>

High-Order Analytical Formulation of Soliton Self-Frequency Shift

<div>We derive an analytical formulation of the Raman-induced frequency shift experienced by a fundamental soliton. By including propagation losses, self-steepening, and dispersion slope, the resulting formulation is a high-order (HO) extension of the well-known Gordon's formula for soliton self-frequency shift (SSFS). The HO-SSFS formula closely agrees with numerical results of the generalized nonlinear Schrödinger equation, but without the computational complexity and required computation time. The HO-SSFS formula is a useful tool for the design and validation of wavelength conversion systems and supercontinuum generation systems.</div>

Design and simulation of strip loaded and rib waveguide with integration of 2D material

Objective- To design Graphene-Silicon based rib waveguide and reduce the losses in the strip in order to meet the requirement for ultra-fast & ultrahigh optical bandwidth communication and computing in integrated optical devices. Method –Propagation losses and effective refractive index are the two key parameters. In order to meet the objective, the effects of Graphene for manufacturing passive devices/components in the field of Integrated Photonic like integrated optical waveguide have been analysed by measuring the changes in propagation losses and effective refractive index of the silicon photonics devices for operating at different wavelengths. Findings- We have presented the design and simulation of SOI (Silicon-on-Insulator) platforms with 2D layer materials (graphene) which has been used along with their mode of propagation, effective refractive index (ne f f ), propagation losses (dB/cm) and varying wavelength range for optimum performance. In addition to this, we have also calculated the boundary limit for both the speed and bandwidth. We also reported the development of Silicon rib waveguide, Graphene-Silicon based rib waveguide and Ge on SOI with graphene later at the top of strip waveguide.Minimum loss of strip waveguide is 2.9 dB/cm which has been obtained for Mid-IR wavelength generally used for high power mid- IR sensing.