Osa determination of the effective refractive index of. A refractive index is a property of the material itself. Increasing cladding refractive index increases the effective refractive index n eff and this generally cause a reduction in the power flow along the fibre see figure 8 figure 9. Lebedev physical institute, moscow, from 1952 to 1983. The concepts behind optical ring resonators are the same as those behind whispering galleries except that they use light and obey the properties behind constructive interference and total internal. Optical constants of inas indium arsenide aspnes and studna 1983. Inserting 1 into the helmholtz wave equation leads to the paraxial wave equation1.
Parametric simulations of slanted 1d photonic crystal sensors. Analysis of straininduced pockels effect in silicon. Whenever light is incident on a dielectric material, like glass, part of the light is transmitted while another part is reflected. Biosensor, refractive index, grating coupler, waveguide. Nanoparticles of transparent conducting oxides, such as indium tin oxide, can be used in printing techniques to generate functional layers for various optoelectronic devices. Jun 06, 2017 whenever light is incident on a dielectric material, like glass, part of the light is transmitted while another part is reflected.
Click on run in browser to start the application you will see that following window opens which has input parameters, description, graphical features and a few buttons. Effective refractive index an overview sciencedirect. By default comsol understands first column position 0 in default as wavelength. Comsol multiphysics, one can compute the effective refractive index neff of the sensor 5 and from it the transmission coefficient t as a function of the wavelength, the external refractive index next and the thickness of the metal dm, according to the expression 2,eff ext 0, ext nndkl tnd em. Can anyone please help me out to find the mode of photonic. Measurement of the effective refractive index of a turbid.
For users of the wave optics module, comsol multiphysics version 5. Rectangle 2 r2 1 on the geometry toolbar, click primitives and choose rectangle. Comsol, we get effective refractive index corresponding to the wavelength and we know that the dispersion parameter is the second order derivative of. Particular functionality may be common to several products. For simple cases, the free software rp fiber calculator is sufficient definition. Analysis of linearly polarized modes comsol multiphysics. An interferometric method is applied to determine the refractive indices of lithium niobate single crystals over a wide wavelength and composition range. Considering this, the effective refractive index is given by 15, 16. How simulate the complex refractive index neff by comsol.
Modeling and simulation of high permittivity coreshell ferroelectric po for enlymers ergy storage solutions. Numerical investigation of a refractive index spr dtype. Electromagnetic waves scattering off of a nano sphere. Then, we can calculate the real part of the refractive index for many branches, as shown in the figure below. For example, glass has a refractive index of about 1. Modeling a negative refractive index wave optics application id.
Microstructures can be used to locally control the airmaterial ratio in a fibre. For the coreguided modes, such solidcore pcfs are effectively step index fibers with an effective refractive index. Download file pdf comsol optical waveguide simulation thank you extremely much for downloading comsol optical waveguide simulation. The effective refractive indices for this model were again calculated using both a comsol direct solver and the dimension reduction. Dec 28, 2011 15 videos play all comsol beginners tutorial daniel martinez comsol simulation tutorial. As this effective refractive index decreases so too does the depth of the bandgap and the.
Effective index is sometimes used to mean modal index, but that is a bad choice of words because effective index is a term used for other things too. Diagonal anisotropy a modal analysis is performed while parametrically sweeping the length of the waveguide from 0. Refractive index database table of refractive index values. How to model the optical properties of rough surfaces.
With this ratio, the effective refractiveindex can be determined. This tutorial demonstrates the use of the optical fibre toolbox for calculation of the threelayer corecladdingsurrounding fibres. The higher the airmaterial fraction, the lower is the resulting effective index. Modelling of optical waveguide using comsol multiphysics. The refractive index of the prism has to be higher than that of the medium under measurement, as otherwise there will be no total internal reflection. These can be, but are not limited to being, waveguides. Veselago victor georgievich graduated from moscow university in 1952, and was with p. Osa calculation of the effective refractiveindex step for.
Now an effective refractive index can be given for an optical component e. The first acoustic metamaterial, also called as locally resonant sonic materials was demonstrated with negative effective dynamic density. On the basis of this generalized sellmeier equation the parameters of nearly all optical. Most likely you have knowledge that, people have look numerous period for their favorite books similar to this comsol optical waveguide simulation, but stop in the works in harmful downloads. Refractive index database the table below contains links to refractive index data for common materials.
Keeping unchanged the refractive index of the core, calculate the minimum refractive index of the cladding for which the fiber is single mode at the wavelength of 1550 nm. The software rp fiber power has a mode solver which calculates effective refractive indices among various other mode properties. Total reflection and transmission by epsilonnearzero metamaterials with defects yadong xu and huanyang chen school of physical science and technology, soochow university, suzhou 215006, china abstract. An optical ring resonator is a set of waveguides in which at least one is a closed loop coupled to some sort of light input and output. The effective refractive index of the sample was calculated from the simulated transmission and reflection coefficients using a standard retrieval procedure 12. How to model the optical properties of rough surfaces comsol. To preserve the continuity of the refractive index, we will need to jump from one branch to another at that point. The insert represents a principle sketch of the parabolic refractive index profile. A common belief is that the effective refractive index of a propagation mode e. The critical coupling shows that no light is passing through the waveguide after the light beam is coupled into the optical ring resonator. The main aim of this investigation is the calculation of effective indexes ei of the following structures.
Watch this archived webinar to see how you can model ray propagation in an optical system with different types of rayboundary interaction, including absorption, refraction, and diffuse and specular reflection. In contrast with the similar csp laser, however, confinement of the lasing mode is achieved by metal reflection instead of excess absorption loss outside the active stripe. Refractive indices of lithium niobate as a function of. Rp photonics encyclopedia effective refractive index, modal. Then the effective refractive index of the guided modes is calculated vs. Browse all of the wave optics module updates below. The amount of required memory and computation time could be improved. In comsol multiphysics, the diffusion process can be simulated directly, which enables the inclusion of anisotropic diffusion coefficients, as is known to be the case for linbo3.
The refractive index of the medium can be either large or small according to various applications and purposes. The modeling results show the high sensitivity of the device for measuring the change in refractive index. Comsol multiphysics uses the finite element method fem mesh creates triangle and tetrahedral shapes on the geometry, creates finite space mesh must be fine enough to give accurate results. Effective medium theory to the description of plasmonic. The native oxide layer that forms in typical ambients must often be taken into account when measuring the thickness or refractive index of very thin films on silicon. The aim is to show basic principles, how to use the tools, how to extract data and so on. A newly developed stripegeometry injection laser is presented with builtin passive waveguiding produced by an effective refractive index step between active stripe and adjoining regions. Santos et al numerical investigation of a refractive index spr dtype optical fiber sensor using comsol multiphysics 63, j iz er er eii 11, j iz hr hr eii 12 where i is the propagation constant of the ith mode, and r is the position vector in the plane. Rapid prototyping of biosensing surface plasmon resonance. This is down to the effective refractive index between the stacks and the medium changing.
Coming to refractive index file which has both n k values, you can import the file and mention n and k positions. Effectiveindex method and coupledmode theory for almost. Introduction the propagation of optical modes in periodic and almostperiodic waveguide gratings is a topic of considerable interest. How i can draw the effective indexwavelength diagram in the. How can i calculate an effective refractive index by using. Modify the model with the obtained value of the refractive index and solve for the wavelength of 1550, 1500 and 1600 nm. Figure 3 shows the evolution of power flow against the change of refractive index. First, the specification of such structures is explained. Effective index method, coupledmode theory, corrugated waveguide gratings. Total reflection and transmission by epsilonnearzero. Apr 29, 2014 since modal index is the quotient of two wave numbers it is dimensionless, like refractive index. How i can draw the effective indexwavelength diagram in. Since 1983 he is head of the laboratory of magnetic materials at the a. Study of bending losses in optical fibers using comsol.
Largesize passive or active eo waveguide structures can be simulated. Sep 27, 20 in this paper, a number of polymeric waveguide structures have been analyzed by using two distinct techniques which are. The user can simulate a design, test for the capacitance and observe the effects on capacitance by changing parameters such as dielectric permittivity of materials. A dispersion curve represents the variation of the effective refractive index with respect to the length of the waveguide or the operating frequency. The article shows that this picture is quite wrong. What is refractive index absolute refractive index. So, we can calculate the different longitudinal acoustic modes in other words the different. Since these deposition methods do not create fully consolidated films, the optical properties of such layers are expected to be notably different from those of the bulk material and should be characterized on their own. Using the mode analysis study in comsol, we computed solutions of this form.
For a large scale waveguide coupler structure, a good agreement. In this work, we investigate wave transmission through an epsilonnearzero metamaterial waveguide embedded with defects. Ray optics module updates for users of the ray optics module, comsol multiphysics version 5. I try to calculate the effective index of photonic crystal fiber. So you need to mention n position 1 and k position 2. As mentioned above, we solve the wave equation in the pcf crosssection. Maxwells equations the next simplest form of the constitutive relations is for simple homogeneous isotropic dielectric and for magnetic materials. Research of dispersion characters in hexagonal photonic.
In the particular case of the pockels effect, also called linear electrooptic effect, the change in the refractive index is proportional to the applied electric field. The measuring prism acts as the refractive index reference. Modal analysis of stepindex single mode fiber optic using. A generalized two term sellmeier equation is proposed that describes the refractive indices as a function of wavelength and stoichiometry. Retrieval center for metamaterials and integrated plasmonics. One more feature about optical coupling is the critical coupling. Is it possible with comsol to define a range of wavelengths with to define its step in order to calculate the effective index. Furthermore, one could use these measurements, together with a speci.
Each material in the database has refractive index listed as a function of wavelength over a range typically required for thinfilm thickness measurement. Effective refractive index calculating effective refractive indices. Below are files of complete refractive index and extinction. Mar 22, 20 keeping unchanged the refractive index of the core, calculate the minimum refractive index of the cladding for which the fiber is single mode at the wavelength of 1550 nm. Dec 04, 2017 a dispersion curve represents the variation of the effective refractive index with respect to the length of the waveguide or the operating frequency. Additionally, is well known that the particles contribution depends on the refractive index, shape and particles size 38. In this video in hindi we proved that the relative refractive index or effective refractive index of second medium with respect to the first medium is the reciprocal of the relative refractive. Comsol multiphysics is used to simulate the biosensor by measuring the refractive index of the binding layer. This will open up comsol library where you see many comsol files to solve chemical reaction engineering problems. Comsol lep tutorial for tank flow system two cstr in series. Capacitive sensor design using comsol provides the user with a wide variety of tools. Sometimes, we add a metal coating, such as gold, which alters the transmittance and reflectance as well as leads to some absorption of light. So for comsol i know only that i can set a single value of wavelength.
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