ISSN 2738-0971 | eISSN 2738-1013
Bulletin of Natural Sciences Research
Open access journal | Double-blind peer review

Branko Drljača

Faculty of Sciences, University of Priština, Kosovska Mitrovica

Articles

Open Access Original Scientific Paper

UNCONDITIONALLY POSITIVE FINITE DIFFERENCE AND STANDARD EXPLICIT FINITE DIFFERENCE SCHEMES FOR POWER FLOW EQUATION

by Branko Drljača, Svetislav Savović

Power flow equation for step-index glass optical fiber was solved using recently reported unconditionally-positive finite difference (UPFD) scheme. Solution obtained using UPFD scheme was compared with solution obtained using standard explicit finite difference (EFD) scheme. For accuracy testing both schemes were compared with analytical solution for steady state distribution of given fiber. The advantage of UPFD is reflected in stability of the scheme regardless of discretization step taken. Nevertheless EFD scheme has better concurrence with analytical solution than UPFD. This is due to the additional truncation-error terms in the approximations of the first and second derivatives with respect to θ.

View Full-Text DOI 10.5937/univtho9-23312 Published: 30 Dec 2019
Open Access Original Scientific Paper

CALCULATION OF THE FREQUENCY RESPONSE AND BANDWIDTH IN LOW NUMERICAL APERTURE STEP-INDEX PLASTIC OPTICAL FIBER USING TIME-DEPENDENT POWER FLOW EQUATION

by Branko Drljača, Slavica Jovanović, Svetislav Savović

Time-dependent power flow equation is employed to calculate frequency response and bandwidth of low numerical aperture step-index optical fiber excited with Gaussian-like light source with large width. Both, frequency response and bandwidth, are specified as function of the fiber length measured from the input end of the fiber. Analytical and numerical solutions are compared and good agreement between results is obtained.

View Full-Text DOI 10.5937/univtho6-12574 Published: 31 Dec 2016
Open Access Original Scientific Paper

THE INFLUENCE OF NONLINEAR AND LINEAR DEFECTS ON THE LIGHT PROPAGATION THROUGH LINEAR ONE-DIMENSIONAL PHOTONIC LATTICE

by Slavica Kuzmanović, Marija Stojanović Krasić, Ana Mančić, Branko Drljača, Milutin Stepić

In this paper, the light beam propagation through one-dimensional photonic lattice, possessing one nonlinear defect and one linear defect, has been investigated numerically. Different dynamical regimes have been identified in terms of the distance between the two defects, position of the incident light beam, the width of linear defect, the values of nonlinearity and presence of the transverse kick. Strong localized modes on the defects, breathing and zig-zag modes in the area between defects have been observed. It has been concluded that the width of the linear defect placed next to the nonlinear one influences localization of the beam at the nonlinear waveguide. On the other hand, the nonlinear defect, regardless of the values of nonlinearity, have a small influence on the beam propagation in photonic lattice. It has been observed that the transverse kick of the initial beam leads to the distortion of localized structures. By launching the light beam towards defects, the reflection of light has been noticed. Presented results can be useful for different applications, such as blocking, filtering and routing of light beam through optical media.

View Full-Text DOI 10.5937/univtho6-12670 Published: 31 Dec 2016