S. Sivabalan

Design and Simulation for Ultra High Soliton Pulse Compression through Photonic Crystal Fiber

In this paper, we intend to investigate the pulse compression through liquid core photonic crystal fiber (LCPCF) by using both finite element method (FEM) and split step Fourier method (SSFM). In order to achieve ultra high pulse compression, we propose new LCPCF design with very high nonlinearity. By using numerical analysis, we investigate the pulse compression, compression ratio and pedestal energy for different core liquids in LCPCF using a generalised nonlinear Schrodinger equation (NLSE). Finally, we compare the results with different designing parameters of PCF.

Designing a refractive index based biosensor using a photonic quasi-crystal fiber

We design a ten-fold photonic quasi-crystal fiber using finite element method. Further, we explore various optical characteristics and exploit them for realizing a biosensor. We achieve a maximum refractive index sensitivity of 29000 nm/RIU and a resolution of 3.4 × 10-6 RIU a sensing range of 1.47-1.48.

Few-cycle pulse generation using low confinement loss solid-core photonic quasi-crystal fiber

We design a solid-core photonic quasi-crystal fiber (SC-PQF) of 6-fold for a wide range of operating wavelengths from 0.3 to 5 μm. Further, we explore the various optical properties, namely, birefringence, group velocity dispersion, confinement loss and nonlinearity for the proposed SC-PQF. We achieve a low dispersion of −13 ps²/km and a high nonlinearity of 480 W⁻¹km⁻¹ for 0.3 μm wavelength. By exploiting these optical properties, we numerically demonstrate the generation of few-cycle optical pulses of pulse width 4.7 fs from 30 fs input pulse using the higher order soliton pulse compression technique.

Design of octagonal core micro-cladding leakage channel fiber with low bending loss

We design a large mode area (LMA) micro-cladding leakage channel fiber (LCF) with an octagonal shaped core for 1.064 μm wavelength. Our numerical simulation shows that very low bending loss at small bend radius can be achieved by scaling up the micro-cladding elements of LCF. Further, the proposed fiber exhibits novel properties such as large effective area (1287 μm2) and very low bending loss of 5.58 × 10−3 dB/m for a bending radius of 5 cm. These interesting properties of the proposed LCF pave the way for developing a compact high power fiber laser and amplifier.

Low dispersion and high nonlinearity microstructured photonic quasicrystal fiber

We propose a six fold solid-core photonic quasicrystal fiber for studying optical properties for wavelengths from 200 to 3000 nm and demonstrate a low dispersion and high nonlinearity at 1060 nm for few-cycle pulse generation.

Designing an eight-fold photonic quasi-crystal fiber for enhancing the efficiency of second harmonic generation

We model 8-fold photonic quasi-crystal fiber (PQF) for computing the relative efficiency of second harmonic generation (SHG). Analysis shows 15% increment in SHG relative efficiency in 8-fold (72.36%W^-1cm^-2) compared to 6-fold (62.96 % W^-1cm^-2) PQF.

Supercontinuum generation in a silicon nanowire embedded spiral photonic crystal fiber

We design a silicon nanowire embedded spiral photonic crystal fiber exhibiting a flattened, anomalous with small third order dispersion and a high nonlinearity and demonstrate supercontinuum spectrum of 500 nm bandwidth at 0.450 μm wavelength.

Generation of bright and dark solitons in photonic nanowire

In this paper, we generate bright as well as dark soliton type ultrashort laser pulses in a photonic nanowire. The pulse evolution in the photonic nanowire is described by higher order nonlinear Schrödinger equation with an additional effect relating to the nonlinear change of group velocity, which, in turn, is proportional to the field intensity. The pulse evolution equation is solved by coupled amplitude-phase method. Further, we calculate the minimum power required for realizing the ultrashort laser pulses. The main crux of this work stems from the generation of ultrashort pulses by an entirely new nonlinear effect involving change of group velocity.