Showing papers on "Coupled mode theory published in 1982"
TL;DR: In this article, a set of equations describing pulse propagation in multimode optical fibers in the presence of an intensity-dependent refractive index is derived by taking advantage of the coupledmode theory usually employed for describing the influence of fiber imperfections on linear propagation.
Abstract: A set of equations describing pulse propagation in multimode optical fibers in the presence of an intensity-dependent refractive index is derived by taking advantage of the coupled-mode theory usually employed for describing the influence of fiber imperfections on linear propagation. This approach takes into account in a natural way the role of the waveguide structure in terms of the propagation constants and the spatial configurations of the propagating modes and can be applied to the most general refractive-index distribution. The conditions under which soliton propagation and longitudinal self-confinement can be achieved are examined.
106 citations
TL;DR: In this article, a new mathematical formalism based on a coupled-mode approach is presented to describe light propagation in birefringent optically active crystals, where an arbitrary light wave in the medium is represented as an expansion in terms of linearly polarized eigenmodes.
Abstract: A new mathematical formalism, based on a coupled-mode approach, is presented to describe light propagation in birefringent optically active crystals. An arbitrary light wave in the medium is represented as an expansion in terms of linearly polarized eigenmodes; explicit solutions of the equations for the coupled-wave amplitudes show how power is transferred between the principal components in the presence of optical activity. The (generally elliptically polarized) eigenmodes of the optically active crystal are also derived by a diagonalization of the coupled-mode equations. The analysis is extended to include electro-optic crystals, yielding a more general, complex coupling parameter. The predictions of the theory are in excellent agreement with spectral-transmission measurements in AgGaS2 near its isoindex point at 497 nm.
35 citations
TL;DR: In this article, the 3 × 2 branching waveguide coupler with three input ports and two output ports has been studied theoretically and analytic output power expressions have been obtained for the three-dimensional 3 × 3 coupler from which they were derived.
Abstract: Gyroscope couplers with three input ports and two output ports which can be implemented in a planar geometry are studied theoretically. Using a local normal mode description in the approximation of coupled mode theory, analytic output power expressions are obtained for the 3 × 2 branching waveguide coupler and the 3 × 2 directional waveguide coupler. When optimized, these devices behave identically to each other and to the three-dimensional 3 × 3 coupler [1] from which they are derived.
23 citations
TL;DR: In this article, the authors derived analytic output power expressions for the 3 X 2 branching waveguide coupler and the 3 × 2 directional waveguide coupling coupler with three input ports and two output ports.
Abstract: Gyroscope couplers with three input ports and two output ports which can be implemented in a planar geometry are studied theoretically. Using a local normal mode description in the approximation of coupled mode theory, analytic output power expressions are obtained for the 3 X 2 branching waveguide coupler and the 3 X 2 directional waveguide coupler. When optimized, these devices behave identically to each other and to the three-dimensional 3 X 3 coupler [1] from which they are derived.
7 citations
TL;DR: In this paper, a coupled amplitude equation is developed for surface acoustic waves (SAW) from coupledmode theory, which accounts for the surface propagating character and bulk decay pattern of the uncoupled modes.
Abstract: A general coupled amplitude equation is developed for surface acoustic waves (SAW) from coupled‐mode theory. The derivation accounts for the surface propagating character and bulk decay pattern of the uncoupled modes. The general equation is applied to interactions arising from the weak nonlinearities of the materials supporting SAW’s. Coupling contants K of the nonlinear interactions are shown to be determined from the nonlinear material constants and normalized particle velocity, electric, and strain fields of the linear normal modes. For conservative coupling, a single coupling constant describes a given three‐wave interaction. For a given mode α, the coupling constant to two other modes (β,γ) scales as the product of the frequencies of modes β and γ (ωβωγ ). Theory shows how one‐dimensional single‐nonlinear‐parameter models can approximately account for multiharmonic generation on YZ‐LiNbO3. Applying the theory to experiments on second‐harmonic generation, we find the nonlinear coupling constant for Y...
6 citations
TL;DR: In this article, a coupledmode theory for the nonlinear interaction among surface plasmon and polariton (SP) waves is presented, in which pump depletion effects are explicitly taken into account.
Abstract: A coupled-mode theory for the nonlinear interaction among surface plasmon and polariton (SP) waves is presented, in which pump depletion effects are explicitly taken into account. It is shown that a substantial power transfer from the SP at fundamental frequency to the SP at the second harmonic is not beyond any experimental possibility, provided a phase-matched configuration is employed. Compensation effects, arising when the SP waves propagate at the interface between two nonlinear media, are also considered.
6 citations
TL;DR: The zero crossing of the birefringence coupled with natural optical activity in certain uniaxial crystals can be utilized to build a narrowband and wide field-of-view filter.
Abstract: The zero crossing of the birefringence coupled with natural optical activity in certain uniaxial crystals can be utilized to build a narrowband and wide field-of-view filter. Coupled mode analysis is employed to investigate the field-of-view and passband characteristics of such a spectral filter.
6 citations
TL;DR: In this article, the statistical coupling characteristics of optical directional couplers subject to random irregularities are studied theoretically by means of coupled mode theory and a new method is used for solving coupled mode equations in which random components of coupling coefficients and phase constants are assumed to be Gaussian random processes with an arbitrary correlation length.
Abstract: Statistical coupling characteristics of optical directional couplers subject to random irregularities are studied theoretically by means of coupled mode theory. A new method is used for solving coupled mode equations in which random components of coupling coefficients and phase constants are assumed to be Gaussian random processes with an arbitrary correlation length. Mean values, variances, and probability distributions of coupled powers in 0-dB and 3-dB directional couplers are presented. The influence of random parameters is made clear. It is seen that tolerance requirements can be relaxed by a proper choice of the average parameters. Discussions about the film waveguide couplers for integrated optics applications are presented.
4 citations
4 citations