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A structural model is proposed for designing an electro-optic polymer microring resonator (MRR) switch array. This device consists of 1 horizontal channel, N vertical channels and N switching elements. Every switching element contains triple series-coupled microrings with identical radii. Parameter optimization and characteristic analysis of the device are carried out under the resonance wavelength of 1550nm by using the coupled mode theory, the microring resonance theory, and the electro-optic modulation theory. The simulation results show that the switching functions can be realized in the N+1 channels by applying different manners of operation voltage on the microrings. The device possesses flat spectral response with a switching voltage of 4.5V, crosstalk of less than –30dB, insertion loss of less than 2.09, 2.47, 3.22 and 4.72dB, and extinction ratio of larger than 26.8, 25.2, 22.9 and 19.8dB for 1×4, 1×8, 1×16 and 1×32 channel structures, respectively. [ABSTRACT FROM AUTHOR]

Abstract: The structure and the principle for the polymer electro-optic microring resonator (MRR) switch are proposed as well as the transfer functions. The structural parameters are optimized; the transmission characteristics are analyzed including the output power, switching time, switching voltage, insertion loss, and crosstalk. When the operation voltage is 0V, the insertion loss and crosstalk are ∼1.2 and −20.2dB, respectively; when the operation voltage is 10.0V, those are ∼0.35 and −20.0dB, respectively. Furthermore, a novel method is presented for analyzing time-domain response of the device and the switching time is determined to be ∼10.71ps. These results indicate the favorable switching functions of the designed device. [Copyright &y& Elsevier]

Abstract: Formulas of the transfer functions and the output power gains are presented, amplifying characteristics are analyzed, and simulation is performed for an Er3+–Yb3+-co-doped microring resonator. Under the pump wavelength of 980nm and the central signal wavelength of 1550nm, the dependence of the output power gain on the amplitude coupling ratio, pump power, signal power, and the dopant concentration is investigated, the output spectra are presented, and the optimization of the device is carried out. Simulated results show that the output power gain of this device is much larger than that of the Er3+–Yb3+-co-doped straight waveguide amplifier (EYCDWA) with the same waveguide parameters. [Copyright &y& Elsevier]

Abstract: In order to analyze the power conversion efficiency (PCE) and the gain characteristics of the phosphate glass Er3+–Yb3+-co-doped waveguide amplifier (EYCDWA), formulas are derived from the rate equations and the light propagation equations under the uniform dopant and the steady-state conditions. In the derivation of these formulas, we have neglected the amplified spontaneous emission (ASE) and have introduced the initial energy transfer efficiency. By using these formulas, the effects of the pump power, signal power and waveguide length on the PCE and the gain characteristics of the EYCDWA are analyzed, and some useful results are obtained in three kinds of pumped styles, i.e. the forward-, backward- and bidirectional pumped styles. [Copyright &y& Elsevier]

Abstract: By using the coupled mode theory, electro-optic modulation theory, conformal transforming method, image method and the proposed transfer matrix technique, novel expressions for the both cases of the low switching frequency and the ultra-high switching frequency are presented for analyzing the transmission powers, rise time, fall time, switching time and switching frequency of the polymer directional coupler electro-optic switches. Simulation results of an application based on the technique show that, the switching voltage and coupling length are about 1.457V and 4.374mm, respectively, and the switching time and cutoff switching frequency are about 32.8ps and 114.7GHz, respectively, for the designed switch. [Copyright &y& Elsevier]

Abstract: Structural model and design technique are proposed for a polymer directional coupler electro-optic switch with rib waveguides and push–pull electrodes, of which the electric field distribution is analyzed by the conformal transforming method and image method. In order to get the minimum mode loss and the minimum switching voltage, the parameters of the waveguide and electrode are optimized, such as the core with, core thickness, buffer layer between the core and the electrode, coupling gap between the waveguides, electrode thickness, electrode width and electrode gap. Switching Characteristics are analyzed, which include the output power, insertion loss, and crosstalk. To realize normal switching function, the fabrication error, spectrum shift, and coupling loss between a single mode fiber (SMF) and the waveguide are discussed. Simulation results show that the coupling length is 3082μm, push–pull switching voltage is 2.14V, insertion loss is less than 1.17dB, and crosstalk is less than −30dB for the designed device. [Copyright &y& Elsevier]

Abstract: Based on the transmission theory, parameter optimization is performed, and effects of fabrication errors on transmission characteristics are analyzed for a 33×33 polymer arrayed waveguide grating (AWG) multiplexer around the central wavelength of 1550.918nm with the wavelength spacing of 0.8nm. Simulated results show that fabrication errors result in the shift of the transmission spectrum, and lead to the increase of the crosstalk compared with the device theoretically designed. Furthermore, accumulation and compensation of fabrication errors are investigated. In order to realize the normal demultiplexing of the fabricated AWG device, the allowed fabrication errors are discussed. [Copyright &y& Elsevier]

Abstract: In terms of the coupled mode theory, novel formulations of the transfer functions are presented for a series-cascaded microring resonator (MRR) array. Using these formulas, transmission characteristics are analyzed and some parameters are optimised for such a polymer device. Simulation results show that when several microrings are serially cascaded to form a MRR array, the passband becomes steep, and the nonresonant light and the crosstalk become weak. [Copyright &y& Elsevier]

Abstract: In terms of the coupled mode theory and the transfer matrix technique, novel formulas of the transfer functions are presented for a 2-D microring resonator array. By using these formulas, transmission characteristics are analyzed for this kind of Si based polymer device. Simulation shows that by means of parallel-cascading multiple microrings in every filter element, the passband can be flattened, and the box-like spectral response can be formed; in terms of series-cascading such several filter elements, the passband becomes precipitous, and the non-resonant light and the crosstalk become weak. [Copyright &y& Elsevier]

Abstract: In terms of the coupled mode theory and transfer matrix technique, novel formulas of the amplitude coupling ratios and transfer functions are presented for a series-coupled microring resonator (MRR) array. By using these formulas, parameters are optimized, and transmission characteristics including the transmission spectrum and the insertion loss are analyzed for a SiN/SiO2 series-coupled MRR array on Si substrate. The box-like spectral response is successfully obtained owing to the proper selection of the amplitude coupling ratio between the channel and the ring, and that between adjacent rings, as well as the number of series-coupled rings. [Copyright &y& Elsevier]

Abstract: In terms of the coupled mode theory (CMT) and the transfer matrix method, we present a technique and relative formulas including the bent coupling coefficient, amplitude coupling ratio, amplitude transmission ratio and propagation power for analyzing the vertical bent coupling between a curved rectangular waveguide and a straight one. Investigations show that the bent coupling appears in an effective coupling region by both sides of the central coupling point. Beyond this effective coupling region, however, the bent coupling is very weak, and the propagation power in the waveguide is closer to a constant. As the bent radius increases, or the thickness of the coupling layer between these two waveguides decreases, this effective coupling region becomes wider, in which the coupling behavior becomes stronger. [Copyright &y& Elsevier]

Abstract: Novel formulas of transfer functions are presented, some parameters are optimized, and bending effect of microrings on characteristics is analyzed for a polymer microring resonant wavelength multiplexer (MRRWM) around the central resonant wavelength of 1.55μm with the wavelength spacing of 1.6nm and with eight vertical output channels. Simulated results show that the bending of microrings causes the variation of the propagation constant, leads to the shift of the transmission spectrum, and increases the insertion loss. A method is proposed for eliminating the shift of the transmission spectrum and realizing the accurate demultiplexing of the device. The polymer MRRWM designed possesses the 3-dB bandwidth of 0.2μm, insertion loss less than 0.57dB, and crosstalk below −20dB for every vertical output channel. [Copyright &y& Elsevier]

Novel formulas of transmission functions are presented, some parameters are optimized, and transmission characteristics are analyzed for a polymer microring resonant wavelength multiplexer around the central wavelength of 1.55 μm with the wavelength spacing of 5.6 nm and with eight vertical output channels. The computed results show that the designed device possesses some excellent features including the 3 dB bandwidth of 0.25 μm, weaker background light of 3.8×10−4, smaller inserted loss of less than 0.6 dB, and lower crosstalk below −20 dB for every vertical output channel. [Copyright &y& Elsevier]

Abstract: In this paper, an efficient technique is proposed to flatten the spectral response of an arrayed waveguide grating (AWG) multiplexer. By subtracting an increment from the core width of odd arrayed waveguides and by adding the same increment to that of even arrayed waveguides, a box-like spectral response can be obtained. Simulated result for a 17×17 polymer AWG shows that the box-like spectral response has a 3-dB bandwidth of 0.5nm, the crosstalk is about or less than −30dB for every output channel, and the spectral shift caused by the mode polarization is about 0.02nm. [Copyright &y& Elsevier]

Based on the perturbation theory, a technique named “equivalent rectangular waveguide method” is presented for analyzing the transmission characteristics of arrayed waveguide grating (AWG) multiplexers with trapezoid core cross-sections. As an example, by using this technique, effects of the trapezoid core cross-section on transmission characteristics are performed for a 33×33 polymer AWG multiplexer around the central wavelength of 1.550918 μm with the wavelength spacing of 0.8 nm. Computed results show that the trapezoid core cross-sections result in the shift of the transmission spectrum, and lead to the increase of the crosstalk compared with the device originally designed with exact rectangular core cross-sections. In order to eliminate the shift of the transmission spectrum, decrease the crosstalk, and further realize the accurate demultiplexing, the redesign of the AWG device is carried out. [Copyright &y& Elsevier]

Theoretical analysis is performed for the loss characteristics of a polymer arrayed waveguide grating (AWG) multiplexer around the central wavelength of 1.55 μm with the wavelength spacing of 1.6 nm. The total loss of the device includes the diffraction loss in the input and output (I/O) slab waveguides, bent loss caused by the AWG and I/O channels, leakage loss resulted from the high refractive index substrate, and propagation loss due to the absorption and scattering of the materials of the device. The effects of some structural parameters on the loss characteristics are investigated and discussed. The computed results show that when we select the core thickness as 4 μm, core width as 6 μm, pitch of adjacent waveguides as 15.5 μm, diffraction order as 50, the number of the arrayed waveguides as 91, that of the I/O channels as 17, confined layer thickness between the core and the substrate as 10 μm, distance between the focal point and the origin as 5500 μm, and central angle between the central waveguide and the x-axis (i.e. the vertical of the symmetrical line of the device) as 60°, the total loss of the device can be dropped to the range 3.79–7.93 dB. [Copyright &y& Elsevier]

Abstract: Parameter optimization is performed, transmission characteristics are analyzed, and effects of fabrication errors are investigated for a lateral coupling microring resonator (MRR). Simulated results show that the fabrication errors result in the shift and shape change of the transmission spectrum compared with the designed case without errors. In order to reduce spectral changes, an efficient compensation method of fabrication errors is investigated. [Copyright &y& Elsevier]

By means of the interpolation and iteration methods to deal with the rate equations and the light propagation equations for the Er 3+ /Yb 3+ codoped waveguide amplifier (EYCDWA), the gain characteristics in the forward, backward, and bidirectional pumped styles are analyzed. In order to obtain high gain, some parameters such as waveguide length, dopant concentration, pump power, and signal power are optimized. The results show that the pump power and signal power are about 50 mW and 1 mW, respectively, the gain is about 6.5 dB for the 2.0 cm-long EYCDWA with an Er 3+ ion concentration of 1.5 × 10 26 m –3 and Yb 3+ ion concentration of 1.9 × 10 27 m –3 . Moreover, the upconversion is investigated for the designed device. [ABSTRACT FROM AUTHOR]