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Mode conversion in two-dimensional magneto-photonic crystal waveguide made by fully compatible optical sol-gel matrix

Kahlouche A., Hocini A., Khedrouche D.

Optica Applicata

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2016

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Vol. 46, nr 4

565--576

EN

In this paper, we have reported a theoretical study of the mode conversion in two-dimensional magneto-photonic crystal waveguide. The structure is formed by a triangular lattice of air holes embedded in a composite matrix SiO2/ZrO2 or SiO2/TiO2. These new magneto-optical materials are developed by organic-inorganic sol-gel process and doped with ferrite of cobalt nanoparticles (CoFe2O4). The modal birefringence and conversion output have been calculated by varying, respectively, the film thickness and the magnetic nanoparticles concentration. The obtained results show an enhancement in the TE-TM mode conversion. Thus, when the amount of cobalt ferrite nanoparticles reaches 39% into sol-gel matrix, the efficiency can reach 95% which proves that such structures have very promising potential for creating integrated optical isolators.

2

Effect of plasma on modal dispersion characteristics of elliptical Bragg waveguide

Prajapati Y., Saini J. P., Chauhan D. S., Singh V.

Opto-Electronics Review

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2014

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Vol. 22, No. 1

16-23

EN

In this paper, the dispersion characteristics of a plasma filled elliptical Bragg waveguide is investigated. The modal characteristic equations of the proposed Bragg waveguide for both ω > ωp and ω < ω p are derived. The effects of plasma frequency, numbers of cladding layers and the eccentricity of elliptical Bragg waveguide on the dispersion characteristics are studied. The analysis shows that the introduction of plasma in the proposed waveguide allows to control the propagation of modes.

3

Uncertainty of the Sagnac interferometer-based measurement of the modal birefringence of polarization maintaining optical fibers

Kaczmarek C.

Optica Applicata

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2012

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Vol. 42, nr 4

875--885

EN

Presented is an analysis of the expanded uncertainty of an indirect measurement of modal birefringence of polarization maintaining fibers, based on the Sagnac interferometer and an optical spectrum analyzer. By using this method it is easy to achieve an expanded measurement uncertainty considerably lower than 1%, at a confidence level of 0.95, in measurements of fibers, whose birefringence is independent of the wavelength, as well as fibers, whose birefringence depends on the wavelength, including birefringent photonic crystal fibers (PCF). Guidelines are given, on how to minimize the measurement uncertainty of modal birefringence of these groups of birefringent fibers.

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Wykorzystanie światła rozproszonego do wyznaczania dwójłomności modowej światłowodów planarnych

Gut K., Herzog T.

Elektronika : konstrukcje, technologie, zastosowania

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2012

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Vol. 53, nr 11

36-37

PL

W ostatnich latach intensywnie rozwijane czujniki światłowodowe. W grupie tych czujników szczególne miejsce zajmują czujniki interferometryczne. W interferometrach różnicowych wykorzystuje się zjawisko zmiany fazy pomiędzy prowadzonymi modami na skutek zmian parametrów optycznych toru światłowodowego. Przy konstrukcji tego typu sensorów podstawowym parametrem jest dwójłomność modowa światłowodu. W pracy przedstawiono metodę wyznaczania dwójłomności modowej światłowodu. Pomiar dwójłomności modowej światłowodów wymaga równoczesnego pobudzenia ortogonalnych modów TE i TM których stałe propagacji są zbliżone. Realizuje się to ustalając odpowiedni stan polaryzacji wiązki wejściowej i kąt wprowadzenia jej do pryzmatu sprzęgającego. Kamera CCD nad światłowodem (poprzez odpowiedni ustawiony polaryzator) rejestruje światło rozproszone. Analiza rozkładu natężenia światła pozwala na wyznaczenie dwójłomności modowej badanego światłowodu.

EN

In recent years, optical waveguide sensors developed intensively. Among these sensors occupy a special place interferometrie sensors. The interferometers are used to the phenomenon of differential phase shift between the ongoing mods due to changes in the optical parameters of waveguide. The design of this type of sensor is a fundamental parameter of the modal birefringence. The paper presents a method for determining the modal birefringence waveguide. Measurement of modal birefringence requires simultaneous excitation of orthogonal modes TE and TM propagation constants which are similar. This is done by setting the appropriate polarization state of the input beam and the angle of the prism is put into the coupling. CCD camera over waveguide (through a polarizer set) records the scattered light Analysis of the scattered light intensity distribution allows us to determine the modal birefringence of the waveguide.