Room-temperature low-threshold low-loss continuous-wave operation of 2.26 μm GaInAsSb/AlGaAsSb quantumwell laser diodes Laser operation at room temperature of self-organized In 0.1 Ga 0.9 As/(GaAs) 6 (AlAs) 1 quantum wires grown on (775)B-oriented GaAs substrates by molecular beam epitaxy

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In this paper, we present two applications of electromagnetic software based on the Method of Lines: the rutile-ring method of dielectrically frequency-temperature compensating a high-Q whispering gallery sapphire resonator and a TE 01γ sapphire resonator with distributed Bragg reflector. These studies are based on the Method of Lines in cylindrical coordinates. Because this method use a 2D1/2 resolution, it is possible to take into account layers with very small thickness. The resonant frequencies, field distribution and quality factors can be calculated by this method. Results of Method of Lines are compared with finite element analysis. I IntroductionSapphire is an extremely low loss material. To confine the field within the sapphire and get a high-Q, One of the solutions is to excite Whispering gallery modes. In order to create an oscillator with frequency stability, the resonator must have the frequency-temperature dependence annulled. To compensate the temperature coefficient of permittivity (TCP) for sapphire, thin rutile rings, with opposite TCP, are placed coaxially at the end faces of a sapphire cylindrical resonator operating in WGE 900 mode [1], [2]. Moreover, Bragg reflection occurs between layers of rutile and sapphire and most of the energy is confined into the sapphire.Because WG modes are high order, resonators have large dimensions and consequently a high density of spurious modes.Unlike, fundamental mode TE 01γ , which has good isolation and low spurious mode density, has significant metallic losses due to the cavity. So to solve this problem, we present a second application for the Method of Lines to a sapphire resonator with distributed Bragg reflector which improve the Qfactor decreasing metallic losses.In this paper, Method of Lines (MOL) [3] is used to calculate the dimensions of sapphire and rutile structures to obtained compensation temperature at 72 K. For the second study, MOL is used to get the best Q-factor for a 9 GHz resonant frequency. Then we compare these results with finite element analysis (FE) [5].

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