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Showing papers on "Total internal reflection published in 2000"


Journal ArticleDOI
TL;DR: In this paper, the authors have designed and fabricated waveguides that incorporate two-dimensional (2-D) photonic crystal geometry for lateral confinement of light, and total internal reflection for vertical confinement.
Abstract: We have designed and fabricated waveguides that incorporate two-dimensional (2-D) photonic crystal geometry for lateral confinement of light, and total internal reflection for vertical confinement. Both square and triangular photonic crystal lattices were analyzed. A three-dimensional (3-D) finite-difference time-domain (FDTD) analysis was used to find design parameters of the photonic crystal and to calculate dispersion relations for the guided modes in the waveguide structure. We have developed a new fabrication technique to define these waveguides into silicon-on-insulator material. The waveguides are suspended in air in order to improve confinement in the vertical direction and symmetry properties of the structure. High-resolution fabrication allowed us to include different types of bends and optical cavities within the waveguides.

439 citations


Journal ArticleDOI
TL;DR: In this article, a simple, fast, and flexible technique to measure optical scattering spectra of individual metallic nanoparticles was developed to measure the effect of particle diameter on the dephasing time of the particle plasmon resonance in gold nanoparticles.
Abstract: We have developed a simple, fast, and flexible technique to measure optical scattering spectra of individual metallic nanoparticles. The particles are placed in an evanescent field produced by total internal reflection of light from a halogen lamp in a glass prism. The light scattered by individual particles is collected using a conventional microscope and is spectrally analyzed by a nitrogen-cooled charge-coupled-device array coupled to a spectrometer. This technique is employed to measure the effect of particle diameter on the dephasing time of the particle plasmon resonance in gold nanoparticles. We also demonstrate the use of this technique for measurements in liquids, which is important for the potential application of particle plasmons in chemical or biological nanosensors.

394 citations


Journal ArticleDOI
TL;DR: In this paper, a two-dimensional confinement by photonic crystals in the plane of propagation, and total internal reflection to achieve confinement in the third dimension were demonstrated. But they were not shown to guide light at 1550 nm around sharp corners where the radius of curvature is similar to the wavelength of light.
Abstract: Photonic crystal planar circuits designed and fabricated in silicon on silicon dioxide are demonstrated Our structures are based on two-dimensional confinement by photonic crystals in the plane of propagation, and total internal reflection to achieve confinement in the third dimension These circuits are shown to guide light at 1550 nm around sharp corners where the radius of curvature is similar to the wavelength of light

390 citations


Journal ArticleDOI
21 Jul 2000-Science
TL;DR: An all-dielectric coaxial waveguide that can overcome problems of polarization rotation and pulse broadening in the transmission of optical light is presented here.
Abstract: An all-dielectric coaxial waveguide that can overcome problems of polarization rotation and pulse broadening in the transmission of optical light is presented here. It consists of a coaxial waveguiding region with a low index of refraction, bounded by two cylindrical, dielectric, multilayer, omnidirectional reflecting mirrors. The waveguide can be designed to support a single mode whose properties are very similar to the unique transverse electromagnetic mode of a traditional metallic coaxial cable. The new mode has radial symmetry and a point of zero dispersion. Moreover, because the light is not confined by total internal reflection, the waveguide can guide light around very sharp corners.

310 citations


Patent
22 Dec 2000
TL;DR: In this paper, an organic light emitting diode containing a first electrode, a second electrode, at least one organic light-emitting layer, and an output coupler which reduces a Fresnel loss is provided.
Abstract: An organic light emitting diode containing a first electrode, a second electrode, at least one organic light emitting layer, and an output coupler which reduces a Fresnel loss is provided. The index of refraction of the output coupler is matched to that of the adjacent layer of the device. The output coupler may be a dimpled transparent material or a composite layer containing light scattering particles to also reduce a critical angle loss.

245 citations


Journal ArticleDOI
TL;DR: In this article, the authors proposed an optical parametric oscillator based on quasiparticle engineering, which is a nonlinear resonator in which a coherent pump wave is converted into coherent "signal" and "idler" waves of different frequency.
Abstract: Semiconductor microcavities can support quasiparticles which are half-light and half-matter with interactions possessed by neither component alone. We show that their distorted dispersion relation forms the basis of a quasiparticle ‘‘trap’’ and elicits extreme enhancements of their nonlinear optical properties. When driven by a continuous wave laser at a critical angle, the quasiparticles are sucked into the trap, condensing into a macroscopic quantum state which efficiently emits light. This device is thus an optical parametric oscillator based on quasiparticle engineering. In contrast to a laser, macroscopic coherence is established in the electronic excitations as well as the light field. This paves the way to new techniques analogous to those established in atomic and superconducting condensates, such as ultrasensitive solid-state interferometers. Parametric oscillators are nonlinear resonators in which a coherent pump wave is converted into coherent ‘‘signal’’ and ‘‘idler’’ waves of different frequency, thus forming the basis for broadband tunable sources and mixers. 1 They have found widespread application in both microwave and optical frequency regions, as well as providing a ‘‘quantum testbed’’ for some of the most profound demonstrations of nonclassi

226 citations


Journal ArticleDOI
TL;DR: In this article, a comprehensive study of mode propagation in a range of different air-silica microstructured fibers is presented, where the spectral characteristics for typical airhole geometry's are explained qualitatively and modeled using beam propagation simulations.
Abstract: We present a comprehensive study of mode propagation in a range of different air-silica microstructured fibers. The inscription of both Bragg and long-period gratings (LPGs) into the photosensitive core region of microstructured air-silica fibers has allowed us to generate complex transmission spectra from a range of fibers with various fill fractions and with increasing air-clad hole diameters. The spectral characteristics for typical air-hole geometry's are explained qualitatively and modeled using beam propagation simulations, where the numerical modeling corroborates the experimental measurements. Specifically, the data reveal the propagation of higher order leaky modes in fibers with periodically spaced air-holes, and relatively small air-fill fraction. And as the air-hole diameter increases, spectra show cladding modes defined solely by the inner air-clad region. We describe these measurements and corresponding simulations and discuss their implications for the understanding of such air-hole structures.

185 citations


Journal ArticleDOI
TL;DR: In this paper, the fabrication and characterisation of photonic crystal (holey) fibres in which multiple cores are created by filling in selected air-holes with glass is described.
Abstract: The authors report the fabrication and characterisation of photonic crystal (‘holey’) fibres in which multiple cores are created by filling in selected air-holes with glass. The guidance mechanism is modified total internal reflection. Using a tunable diode laser, the inter-core coupling is investigated as a function of air-hole spacing.

154 citations


Patent
26 May 2000
TL;DR: In this paper, charged particles suspended in a medium such as FluorinertTM Electronic Liquid are used to electrophoretically control total internal reflection (TIR) at a retro-reflective surface formed on a high refractive index material.
Abstract: Charged particles (21) suspended in a medium (20) such as FluorinertTM Electronic Liquid are used to electrophoretically control total internal reflection (TIR) at a retro-reflective surface formed on a high refractive index material. Prismatic structures (35, 32, 81) redirect ambient light from an overhead light source toward a display image and then from the image to the region in front of the image, yielding a high contrast reflective display. A transparent planar waveguide (36) front lights the display with sequential flashes of red, blue and green light to generate a full colour display. TIR can also be controlled at retro-reflective surfaces by means of a vapour-liquid phase transition, or by changing the absorption coefficient of a material using electrical, chemical and/or electrochemical methods.

145 citations


Patent
10 Feb 2000
TL;DR: In this article, a system of coupling optical energy in a waveguide mode, into a resonator that operates in a whispering gallery mode is described, where the fiber is cleaved at an angle Φ which causes total internal reflection within the fiber.
Abstract: A system of coupling optical energy in a waveguide mode, into a resonator that operates in a whispering gallery mode. A first part of the operation uses a fiber in its waveguide mode to couple information into a resonator e.g. a microsphere. The fiber is cleaved at an angle Φ which causes total internal reflection within the fiber. The energy in the fiber then forms an evanescent field and a microsphere is placed in the area of the evanescent field. If the microsphere resonance is resonant with energy in the fiber, then the information in the fiber is effectively transferred to the microsphere.

141 citations


Journal ArticleDOI
TL;DR: A new type of thin-film polarizing beam splitter (PBS) is proposed that is based on the effects of light interference and frustrated total internal reflection that has a significantly better performance than conventional thin- film PBS's.
Abstract: A new type of thin-film polarizing beam splitter (PBS) is proposed that is based on the effects of light interference and frustrated total internal reflection. This PBS has a significantly better performance than conventional thin-film PBS’s. It is nonabsorbing, broadband, and wide angle and has high extinction ratios in both the transmitted and the reflected beams. The principles and theory of this PBS are described in detail. Several PBS’s designed for the visible and the infrared spectral regions are described. The measured results for a prototype visible PBS of this type are presented as well.

Journal ArticleDOI
TL;DR: Experimental results strongly suggest that the first detected signal corresponds to the lateral wave predicted by theory, and the transducer-sample and the transmitter-receiver distances were chosen such that the lateralWave is the first arriving signal.
Abstract: Ultrasonic wave propagation in human cortical bone has been investigated in vitro using the so-called axial transmission technique. This technique, which relies on velocity measurement of the first arriving signal, has been used in earlier investigations to study bone status during fracture healing or osteoporosis. Two quasi-point-source elements, one transmitter and one receiver (central frequency 0.5 MHz), were used to generate a wide ultrasonic beam, part of which strikes the sample surface at the longitudinal critical angle, and to receive the signals reflected from the sample surface. The analysis of the field reflected from a fluid-solid interface for an incident spherical wave predicts the existence of a lateral wave propagating along the sample surface at a velocity close to the longitudinal velocity, in addition to the ordinary reflected wave and vibration modes. The transducer-sample and the transmitter-receiver distances were chosen such that the lateral wave is the first arriving signal. Validation of the measuring technique was performed on test materials and was followed by experiments on human cortical bones. Experimental results (arrival time and velocity) strongly suggest that the first detected signal corresponds to the lateral wave predicted by theory.

Journal ArticleDOI
TL;DR: In this article, the authors studied the effect of one or two thermal relaxation times on the reflection plane harmonic waves of a homogeneous, isotropic, and thermally conducting elastic solid.
Abstract: We discuss the reflection of thermoelastic plane waves at a solid half-space nearby a vacuum. We use the generalized thermoelastic waves to study the effects of one or two thermal relaxation times on the reflection plane harmonic waves. The study considered the thermal and the elastic waves of small amplitudes in a homogeneous, isotropic, and thermally conducting elastic solid. The expressions for the reflection coefficients, which are the ratio of the amplitudes of the reflected waves to the amplitude of the incident waves are obtained. It has been shown, analytically, that the elastic waves are modified due to the thermal effect. The reflection coefficients of a shear wave that incident from within the solid on its boundary, which depend on the thermoelastic coupling factor and included the thermal relaxation times, have been found in the general case. The numerical values of reflection coefficients against the angle of incidence for different values of thermal relaxation times have been calculated and the results are given in the form of graphs. Some special cases of reflection have also been discussed, for example, in the absence of thermal effect our results reduce to the ordinary pure elastic case.

Journal ArticleDOI
TL;DR: Tunneling of photons in frustrated total internal reflection has been studied in the time domain with single-cycle femtosecond pulses and it is found that superluminal signal propagation is not possible in this case because of the inevitable diffractive spreading of the signal beam.
Abstract: Tunneling of photons in frustrated total internal reflection has been studied in the time domain with single-cycle femtosecond pulses. It is seen that both the phase and energy of the pulse travel faster than the speed of light in vacuum. Theoretical analysis of the experiments shows that the time-response function for electromagnetic waves propagating in the air gap is noncausal. However, it is found that superluminal signal propagation is not possible in this case because of the inevitable diffractive spreading of the signal beam.

Journal ArticleDOI
TL;DR: In this article, a TPD/ALq3 structure with a typical intrinsic emission spectrum, embedded in a microcavity with a thick and a semitransparent silver mirror, the integrated emission in air, the color variation with angle, and the change in the decay time are compared with those in a DBR-based microcave.
Abstract: Microcavities for organic light-emitting devices (OLED’s) with a metal mirror on one side and a distributed Bragg reflector (DBR) on the other side have been extensively studied in the literature. Usually the DBR is highly reflective, and the resulting emission of the microcavity depends strongly on angle and wavelength. With a thick metal mirror on one side and a semi-transparent metal mirror on the other side of the OLED, a microcavity can be obtained with an optical thickness of 1 half-wavelength. Because the emission is enhanced over a wide solid angle, with a small spectral dependence, this structure is very promising for display applications. For a TPD/ALq3 structure with a typical intrinsic emission spectrum, embedded in a microcavity with a thick and a semitransparent silver mirror, the integrated emission in air, the color variation with angle, and the change in the decay time are compared with those in a DBR-based microcavity.

Patent
28 Nov 2000
TL;DR: In this article, a prism 4 and a light transmitting plate 3 are arranged inclusively between a pupil plane 1 and an image plane 5, and the light transmission plate 3 has holographic elements (HOEs) 61 to 64 on both surfaces respectively of an incident region and of an exit region.
Abstract: PROBLEM TO BE SOLVED: To provide an observation optical system or imaging optical system which can be made as small as, being usable for a portable telephone and portable information terminal as well as a virtual image observation apparatus of a head-worn type, is light in weight and bright, has moreover high resolution and is easily manufactured. SOLUTION: A prism 4 and a light transmitting plate 3 are arranged inclusively between a pupil plane 1 and an image plane 5. The light transmission plate 3 has holographic elements (HOEs) 61 to 64 on both surfaces respectively of an incident region and of an exit region, and totally reflect luminous fluxes >=10 times inside the light transmitting plate. The HOEs 61 and 62 are formed so as to respectively diffract the incident luminous fluxes, until the incident angles attain angles which exceed the total reflection critical angle of the light transmitting plate. HOEs 63 and 64 are formed so as to respectively diffract the luminous fluxes introduced to the exit region, until the incident angles attain the angles do not exceed the total reflection critical angle of the light transmitting plate. The prism 4 has a curved surface for correcting the eccentric aberrations of the luminous fluxes, emitted from the light transmitting plate 3.

Journal ArticleDOI
TL;DR: The conventional Fabry-Perot resonator is shown to be a special case of this general class of cavities that have uniform polygonal geometries and have significant applications in a wide variety of optical devices.
Abstract: A general class of multifacet optical resonators that have uniform polygonal geometries is described. Expressions for the transmission of light through classical refractive escape from the cavities are presented. The conventional Fabry–Perot resonator is shown to be a special case of this general class of cavities. The effects of absorption and scattering of optical radiation on the transmission properties and cavity-quality factors are analyzed. These resonator structures have significant applications in a wide variety of optical devices.

Patent
27 Dec 2000
TL;DR: In this article, a side-emitting illumination device for uniformly distributing light is composed of an LED light source, a light-transmitting rod which permits total internal reflection, and outcoupling material affixed to an outer surface of the rod.
Abstract: According to this invention, a side-emitting illumination device for uniformly distributing light is composed of an LED light source, a light-transmitting rod which permits total internal reflection, and outcoupling material affixed to an outer surface of the rod. Light enters the rod at one end and travels along the rod by total internal reflection. Light that hits the outcoupling material is angularly distributed based on the width of the outcoupling material.

Journal ArticleDOI
TL;DR: In this article, strong angular-dependent emission properties are observed from a semiconductor microcavity pumped along a critical angle of incidence, and the emission is completely asymmetrical with respect to the sample normal.
Abstract: Strongly angular-dependent emission properties are observed from a semiconductor microcavity pumped along a critical angle of incidence. In contrast to the luminescence from conventional semiconductor heterostructures, the emission is completely asymmetrical with respect to the sample normal. The results imply that parametric scattering dominates the energy relaxation of polaritons, and is enhanced by the deformed shape of the dispersion relations.

Journal ArticleDOI
TL;DR: In this paper, the anomalous dispersion (AD) of water at the interface between the optical element and bulk solution was modeled with approximation-free calculations, and the modeled spectra were compared with experimental ATR spectra for different internal reflection elements.
Abstract: The distortion of band shapes seen in infrared attenuated total reflection (IR-ATR) spectroscopy of strongly absorbing materials such as water, relative to transmission sampling, is shown here to be due to the anomalous dispersion (AD) of water. This distortion occurs in addition to the normal 1/upsilon dependence, and, contrary to previous reports, is shown to not be due to chemical changes of water at the interface between the optical element and bulk solution. IR-ATR spectra of water were modeled with approximation-free calculations. The modeled spectra are compared with experimental ATR spectra for different internal reflection elements, and the results are discussed in terms of the AD optical effect.

Journal ArticleDOI
TL;DR: In this paper, the force of light upon a metallic particle is computed based on both the stress tensor and the couple dipole method, and the behavior of this force on either a small or a large particle in terms of the wavelength is analyzed.
Abstract: By using a method, previously established, to calculate electromagnetic fields, we compute the force of light upon a metallic particle. This procedure is based on both Maxwell's stress tensor and the couple dipole method. With these tools, we study the force when the particle is over a flat dielectric surface. The multiple interaction of light between the particle and the surface is fully taken into account. The wave illuminating the particle is either evanescent or propagating depending an whether or not total internal reflection takes place. We analyze the behavior of this force on either a small or a large particle in terms of the wavelength. A remarkable result obtained for evanescent field illumination is that the force on a small silver particle can be either attractive or repulsive depending on the wavelength. This behavior also varies as the particle becomes larger.

Journal ArticleDOI
14 Jan 2000-Langmuir
TL;DR: In this article, total internal reflection sum-frequency spectroscopy (TIR−SFS) was used to detect molecules adsorbed on ultrathin gold films (≤10 nm) deposited on a sapphire prism.
Abstract: Total internal reflection sum-frequency spectroscopy (TIR−SFS) is shown to be capable of detecting molecules adsorbed on ultrathin gold films (≤10 nm) deposited on a sapphire prism. Octadecanethiol (ODT) and thiocyanate (SCN-) were used as probe molecules in order to assess the usefulness of the approach. For ODT adsorbed on 5-nm Au films, SF signal enhancements of over an order of magnitude were observed with TIR−SFS compared to the standard external reflection geometry. While TIR−SF spectra were obtained for ODT on 5- and 10-nm Au films, no molecular signals were detected for 20-nm Au films. The C⋮N stretch of SCN- adsorbed on a 5-nm Au film was detected by TIR−SFS in the presence of either water or air. A theoretical model is presented to rationalize the different SF signal levels observed under various conditions. Future prospects of TIR−SFS for studying other oxide-supported metals are discussed, along with possible applications in the fields of heterogeneous catalysis and electrochemistry.

Journal ArticleDOI
TL;DR: An optical resonator is characterized that employs both ultrahigh-reflective coated surfaces and total internal reflection to enable cavity ringdown spectroscopy of surfaces, films, and liquids to enable polarization-dependent phenomena, such as molecular orientation, to be probed.
Abstract: An optical resonator is characterized that employs both ultrahigh-reflective coated surfaces and total internal reflection to enable cavity ringdown spectroscopy of surfaces, films, and liquids. The monolithic folded design possesses a polarization-independent finesse that allows polarization-dependent phenomena, such as molecular orientation, to be probed. Although a restricted bandwidth (∼15% of the design wavelength) results from use of reflective coatings, the resonator provides high sensitivity and facile operation. A minimum detectable absorption of 2.2 × 10-6 was obtained for single laser shots by use of multimode excitation at 530 nm with an excimer-pumped, pulsed dye laser.

Journal ArticleDOI
TL;DR: It is shown that absorption leads to specific changes in the value of reflectivity near the SPR angle and that these can be used for absorbance detection and has the potential for substance-specific detection.
Abstract: The effect of absorption of the sample medium on the surface-plasmon resonance (SPR) characteristics is analyzed by approximate analytical and exact numerical models. We show that absorption leads to specific changes in the value of reflectivity near the SPR angle and that these can be used for absorbance detection. The strongest absorption-induced change in reflectivity occurs at two values of metal film thickness (28 and 55 nm for a gold film and lambda = 632.8 nm). Using a sample solution of Rhodamine 700 in ethanol, we measured the characteristic changes in the SPR angle and in reflectivity over the wavelength interval encompassing the strong absorption band at 610-680 nm. The possibility of the simultaneous determination of the refractive index and absorption from SPR measurements is demonstrated and has the potential for substance-specific detection.

Proceedings ArticleDOI
13 Jun 2000
TL;DR: In this paper, the dispersive relations of refractive index of human whole blood with different types in the visible and near-infrared ranges and other conditions were analyzed using a focused light, a semicylindrical lens in contact with tissues and a linear CCD camera.
Abstract: Knowledge of the optical properties of human whole blood has always been of great interest for medical applications. The aim of this study was to provide the dispersive relations of refractive index of human whole blood with different types in the visible and near-infrared ranges and other conditions. In order to overcome the scattering effect, we applied an unusual method based on total internal reflection. A focused light, a semicylindrical lens in contact with tissues and a linear CCD camera are used in the experimental apparatus. The critical angle and therefore the refractive index can be obtained from the spacial distribution of internal reflective light. A monochromator is chosen as the light source, the chromatic dispersion curve of materials can be determined directly and quickly. A set of values has been presented that relates the refractive index to wavelength and types of whole, undiluted blood. Our results suggest that the refractive dispersions be almost the same in the visible and near-infrared ranges no matter which blood type it belongs to. In addition, the relationship can be described by Cauchy's formula.

Journal ArticleDOI
TL;DR: In this article, the authors studied the scattering of an acoustic wave incident on a transversely isotropic cylinder immersed in a fluid and found that the form function is rich in peaks whose number steadily goes down as the angle of incidence increases.

Journal ArticleDOI
TL;DR: In this paper, a planar photonic crystal, PPC, is considered and three-dimensional band structure calculations show that a PPC supporting only a few guided modes (by keeping the thickness of the PPC small enough) can have a photonic band gap.

Journal ArticleDOI
TL;DR: In this article, a unified analytical treatment of the radiation from an electric dipole of arbitrary orientation embedded at an arbitrary location within a symmetrically clad dielectric slab is presented.
Abstract: A unified analytical treatment of the radiation from an electric dipole of arbitrary orientation embedded at an arbitrary location within a symmetrically clad dielectric slab is presented. Both the emission into three-dimensional (3-D) radiation modes, corresponding to emission within the critical angle escape cone within the dielectric slab, and into the two-dimensional (2-D) waveguide modes are evaluated from a single calculation. The model is valid for arbitrary dielectric contrast between the slab and the cladding. The mathematical approach uses well-known complex analysis techniques: the 3-D radiation is described by a steepest descents integration around branch cuts while the 2-D waveguide modes correspond to simple poles. The division of the radiated power between the 3-D and 2-D modes is evaluated across the entire range from small dielectric contrast appropriate to diode lasers (/spl lsim/1,1) to the very large dielectric contrast of free-standing semiconductor slabs (/spl sim/12-19). Both enhancement and suppression, depending on position, slab width, dielectric contrast, and wavelength, of the total radiated power in comparison with that in an unbounded dielectric-medium are found for slab widths on the order of a wavelength with a maximum enhancement of /spl sim/30% for these one-dimensional Fabry-Perot structures. For thicker slabs the total radiation is almost constant and equal to that in the unbounded medium for low dielectric contrast while still exhibiting some modulation as increasing thickness allows additional waveguide modes.

Journal ArticleDOI
TL;DR: Three-dimensional reconstruction of the fluorophore distribution from angle-resolved image stacks results in topographical information with an axial resolution of tens of nanometers to study the axial position of dye-labeled subcellular storage organelles ('vesicles') in the "footprint" region of living neuroendocrine cells grown on the interface.
Abstract: The evanescent wave (EW) elicited by total internal reflection of light selectively excites fluorophores in an optical slice above a reflecting dielectric interface. EW excitation eliminates out-of-focus fluorescence present in epiillumination microscopy, and--close to the coverslip--can offer a fivefold enhancement of axial optical sectioning compared to confocal and two-photon microscopy. The decay length of the evanescent field is a function of the refractive indices and light wavelength involved, and is modulated by the beam angle. EW microscopy was used to study the distribution and concentration of fluorophores at or near the interface in the presence of high concentrations in bulk solution. We modified an upright microscope to accommodate the condenser optics needed for EW excitation. Systematic variations of the angle of incidence were attained using an acousto-optical deflector, telecentric optics, and a hemicylindrical prism. The three-dimensional reconstruction of the fluorophore distribution from angle-resolved image stacks results in topographical information with an axial resolution of tens of nanometers. We applied this technique to study the axial position of dye-labeled subcellular storage organelles ('vesicles') of approximately 300 nm diameter in the "footprint" region of living neuroendocrine cells grown on the interface.

Journal ArticleDOI
TL;DR: In this paper, complex representations of the propagation operator by choosing either a complex reference wave number or a complex representation of Pade approximation are proposed to solve the problem of inaccuracy and instability.
Abstract: Existing algorithms for bidirectional optical beam propagation proposed to simulate reflective integrated photonic devices do not propagate evanescent fields correctly. Thus inaccuracy and instability problems can arise when fields have significant evanescent character. We propose complex representations of the propagation operator by choosing either a complex reference wave number or a complex representation of Pade approximation to address this issue. Therefore correct evolution of both propagating waves and evanescent waves can be simultaneously realized, significantly reducing the inaccuracy and instability problems. Both test problems and practical problems are presented for demonstration.