Wyniki wyszukiwania - Biblioteka Nauki

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Model generacji promieniowania w laserach DBR z ośrodkiem w postaci planarnego światłowodu fotonicznego

100%

Mossakowska-Wyszyńska A.

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2008

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tom Vol. 49, nr 9

46-49

PL

W pracy zaprezentowano po raz pierwszy analizę generacji promieniowania w laserach DBR z ośrodkiem w postaci planarnego światłowodu fotonicznego. Zaproponowano ogólny model działania wymienionych laserów, uwzględniający zarówno podłużny, jak i poprzeczny rozkład pola w rezonatorze otoczonym zwierciadłami wykonanymi w postaci jednowymiarowych kryształów fotonicznych. Korzystając z metody opartej na bilansie mocy w strukturze i przybliżeniu rozkładów progowych, uzyskano analityczny związek pomiędzy małosygnałowym wzmocnieniem, a mocą wyjściową i charakterystycznymi parametrami rozpatrywanego układu laserowego. Zaprezentowano charakterystyki laserowe ilustrujące wpływ parametrów zwierciadeł wykonanych w postaci jednowymiarowych kryształów fotonicznych na znormalizowany współczynnik małosygnałowego wzmocnienia. Zaproponowany rodzaj struktur laserowych charakteryzuje się większą mocą wyjściową niż klasyczne struktury falowodowe.

EN

In this paper, we present an analysis of the nonlinear operation of planar waveguide laser with 1D photonic crystal mirrors. In our theoretical model, we take into account the gain saturation effect, transverse and longitudinal field distribution. With the help of an energy theorem and threshold field approximation, we obtain an approximate formula relating small-signal gain to the output power and laser parameters such as parasitic losses in the active medium and photonic crystal cell geometry. With the help of this relation, laser characteristic showing an optimal reflection of 1D photonic crystal mirrors and optimal geometry of the waveguide structure, which provide maximal power efficiency for a given laser structure, are obtained. It is shown, that this kind of laser structure can provide single mode operation and higher output power level than analogues classical waveguide laser structure.

2

Investigation and modelling of rare-earth activated waveguide structures

45%

Woliński W. , Malinowski M. , Mossakowska-Wyszyńska A. , Piramidowicz R. , Szczepański P.

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tom Vol. 53, nr 2

97-102

EN

In this paper the overview of the recent study on the rare-earth activated waveguides performed in the Optoelectronic Department of IMiO is presented. We reported on the development of rare earth-doped fluorozirconate (ZBLAN) glass fibers that allow a construction of a new family of visible and ultraviolet fiber lasers pumped by upconversion. Especially the performance of holmium devices is presented. The properties of laser planar waveguides obtained by the LPE process and the growth conditions of rare earths doped YAG layers are presented. In this paper we present also the theoretical study of the nonlinear operation of planar waveguide laser, as an example the micro disk Nd:YAG structure is discussed. We derived an approximate formula which relates the small signal gain in the Nd:YAG active medium and the laser characteristics, obtained for whispering-gallery modes and radial modes, to the output power and real parameters of the laser structure

3

Semi-analytical model of Raman generation in silicon-on-insulator rib waveguide with DBR/F-P resonator

45%

Tyszka-Zawadzka A. , Szczepański P. , Mossakowska-Wyszyńska A. , Karpierz M. , Bugaj M.

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tom Vol. 21, No. 4

382-389

EN

An approximate method of modelling of Raman generation in silicon-on-insulator (SOI) rib waveguide with DBR/F-P resonator including spatial field distribution and nonlinear effects such as Raman amplification and two photon absorption (TPA), is developed. In threshold analysis of steady-state Raman laser operation, an analytical formula relating threshold pump power to the system parameters is obtained. The analysis of the above threshold operation is based on an energy theorem. In exact energy conservation relation, we approximate the Stokes field distributions by that existing at the threshold, whereas the approximate pump field distributions are obtained by integrating the equations for the pump signal using the linear (threshold) pump field distributions and the threshold Stokes field distributions. An approximate, semi-analytical expression related the Raman output power to the pump power and system parameters is derived. Our calculations remain in a good agreement with the exact numerical solutions.