An ARROW optical wavelength filter: design and analysis

A novel ARROW (antiresonant reflecting optical waveguide)-based optical wavelength filter is proposed. The modal characteristics of the coupled ARROW structures is analyzed rigorously by the transverse resonance method. As an alternative configuration to the conventional directional coupler filter, the proposed device features large core size compatible with fiber and nearly periodic dependence of the coupling-length on the waveguide separation, which provides more flexibility for fabrication of the device. A design procedure for this type of coupled ARROW structure used for wavelength filtering is presented. The devices designed are simulated and verified by the beam propagation method. An ARROW wavelength filter based on SiO₂/TiO₂ has a FWHM bandwidth narrower than 7 Å     

Low-loss polyimide-Ta2O5-SiO2hybrid ARROW waveguides

A low-loss polyimide-Ta₂O₅-SiO₂ hybrid antiresonant reflecting optical waveguide (ARROW) is presented. The ARROW device was fabricated using both the organic and dielectric thin-film technologies. It consists of the fluorinated polyimide, tantalum pentoxide (Ta₂O₅), and silicon dioxide (SiO₂) hybrid layers deposited on a Si substrate. For transverse electric polarized light, the propagation loss of the waveguide as low as 0.4 dB/cm was obtained at 1.31 μm. The propagation loss for transverse magnetic polarized light is 1.5 dB/cm. An ARROW waveguide fabricated using the polyimide-Ta₂O₅ -polyimide material system is also presented for comparison     

Scattering loss of antiresonant reflecting optical waveguides

The scattering loss of two-dimensional antiresonant reflecting optical waveguides (ARROW) and of ARROW-B, which has a similar structure to ARROW and less polarization dependence, are analyzed by the first-order perturbation theory. Calculated results are compared with those of conventional three layer waveguides. Optimum design for the reduction of scattering loss of these ARROW-type waveguides is discussed. It was found that the scattering loss of ARROW-type waveguides is no larger than that of a conventional waveguide having a relative refractive-index difference, Δ of 2.5%, despite each interface of ARROW-type waveguides having a large Δ, normally larger than 20%. The optimum design for the reduction of essential radiation loss of ARROW is also optimum for the reduction of scattering loss     

Polyimide/Ta2O5/polyimide antiresonantreflecting optical waveguides

A novel antiresonant reflecting optical waveguide (ARROW) fabricated using both the organic and dielectric thin film technologies is presented for the first time. The ARROW consisted of the fluorinated polyimide and tantalum pentoxide (Ta₂O₅) hybrid layers deposited on a Si substrate. For TE polarized light, the propagation loss of the waveguide as low as 0.8 dB/cm is obtained at 632.8 nm. The propagation loss for TM polarized light is 2.7 dB/cm. Some design considerations of the hybrid ARROW are also discussed in this work     

Loss reduction of an ARROW waveguide in shorter wavelength and itsstack configuration

The reduction of the propagation loss of an antiresonant reflecting optical waveguide (ARROW) to 0.3 dB/cm in a short-wavelength band by using transparent TiO₂/SiO₂ interference cladding is discussed. An analysis method for ARROW is developed to analyze its propagation characteristics. Two uncoupled parallel ARROWs were stacked with 2-μm spacing, to obtain three-dimensional optical interconnection     

Hybrid polyimide/Ta2O5/polyimide antiresonantreflecting optical waveguides

A hybrid polyimide/Ta₂O₅/polyimide antiresonant reflecting optical waveguide (ARROW) is presented. The ARROW consists of fluorinated polyimide and tantalum pentoxide hybrid layers deposited on Si substrates. The propagation losses of the device are 0.6 and 2.6 dB/cm at 1.3 μm for TE and TM polarised lights, respectively     

Transient response of ARROW VCSELs under external optical feedback

The effect of external optical feedback on the transient response of antiresonant reflecting optical waveguide (ARROW) vertical-cavity surface-emitting lasers (VCSELs) is studied. It can be shown that the proper design of ARROW can suppress the excitation of high-order transverse leaky mode as well as increase the critical feedback strength so that stable high-power single-mode operation of VCSELs can be obtained even under the influence of strong external optical feedback.     

The model characteristics of ARROW structures

The model characteristics of antiresonant reflecting optical waveguide (ARROW) structures are analyzed by the transverse resonance method as well as some approximate methods. The difference between leaky modes and quasi-guided modes is investigated, and several formulas to calculate the attenuation coefficients of the modes are compared and validated for the ARROW structures. The effects of tunneling leakage and material absorption on the dispersion and the attenuation of the modes are examined in the analysis     

IC compatible optical coupling techniques for integration of ARROWwith photodetector

New structures for efficient coupling of light from an antiresonant reflecting optical waveguide (ARROW) to integrated photodiode are proposed and analyzed. Both end-fire and leaky-wave types of coupling have been considered and it is found that high-coupling efficiencies can be achieved by exploiting the intrinsic properties of the ARROW structure without requiring additional non-IC compatible materials. The coupling structures were simulated using a simple ray optics model as well as the beam propagation method (BPM). Fabrication process conditions and measurement results for various coupling structures are presented     

新型反谐振反射光波导传感器的研究

为了寻找到性能更好、灵敏度更高的光波导传感器,在传统反谐振反射光波导结构的基础之上,提出了一种新型反谐振反射光波导传感器,对其反射率和传输损耗进行了模拟,并计算了它的灵敏度.结果表明,与传统表面均匀传感型反谐振反射光波导传感器相比,新型传感器直接将待测的样品作为波导层并且采用了周期结构的反共振层,使大部分光束集中在样品中传播,从而降低了传输损耗,提高了传感器的灵敏度,为波导传感器的制作提供了一定的数值参考.     

59-nm trimming of center wavelength of ARROW-type vertical couplerfilter by UV irradiation

An antiresonant reflecting optical waveguide (ARROW)-type vertical coupler filter (VCF) with a polysilane cover layer is designed and fabricated to demonstrate the trimming of the center wavelength of the filter by ultraviolet (UV) irradiation. The propagation constant of the upper waveguide of the VCF was modified by UV irradiation on the polysilane cover in the presence of oxygen. The refractive index of polysilane can be adjusted from 1.448 to 1.427 by the exposure time of the UV irradiation. A wide trimming range of 59 nm (1567.5 nm to 1508.8 nm) of center wavelength is demonstrated     

Some effects of anisotropy on planar antiresonant reflectingoptical waveguides

In this paper, propagation characteristics of some planar antiresonant reflecting optical waveguides (ARROW's) comprised of anisotropic media are studied using an integral equation approach. The integral equation method is rigorous and general, with the added advantage that multiple layers of crystalline material with arbitrary anisotropy can be accommodated in a straightforward manner. The integral equation method is applied to study basic propagation characteristics of the ARROW structure where one or more dielectric layers are allowed to be anisotropic. Practically, the presence of anisotropy may be unintentional, due to material fabrication or processing techniques, or it may be intentionally utilized to allow integration of anisotropy-based devices and waveguiding structures on a single semiconducting substrate. Propagation characteristics and field distributions are shown for a uniaxially anisotropic ARROW where the material's optic axis is rotated in each of the three principal geometrical planes of the structure. It Is found that even moderately large levels of anisotropy do not significantly affect the propagation characteristics of the ARROW if either the optic axis of the material is aligned with one of the geometrical axes of the waveguide, or if the optic axis is rotated in the equatorial plane. In these cases, pure TE ₀ modes can propagate, resulting in a low-loss structure. In the event of misalignment between the geometrical axes and the material's optic axis in the transverse or polar planes, the influeuce of even small levels of anisotropy is quite pronounced. In this case, pure TE₀ modes do not exist, and attenuation loss increases significantly due to the hybrid nature of the fundamental mode     

Compact ARROW-type vertical coupler filter

Compact wavelength filter utilizing the vertical coupling between a conventional ridge waveguide and a 3-D ARROW is proposed and demonstrated. Compact size and narrowband performance are achieved utilizing the large difference of waveguide dispersion between the 3-D ARROW and the ridge waveguide at single mode. A polyimide ridge waveguide was stacked on a stripe lateral confinement ARROW in an intersecting configuration with the interaction length of about 1 mm, and -3-dB linewidth of 5.5 nm was experimentally achieved.     

A GaAlAs-GaAs integrated coherence modulator

This paper presents a novel integrated III-V semiconductor waveguide modulator specially designed to generate optical delays of several hundred micrometers. This is achieved by simultaneous propagation of transverse electric (TE) and transverse magnetic (TM) lowest order modes in an original layered waveguide exhibiting a group birefringence greater than 0.02 at 1.3 μm. The device has 40% contrast, a switching voltage of 7 V with a 10-mm long electrode and is suitable for transmission and multiplexing of signals by coherence modulation of light in an optical fiber network powered by a short coherence source such as a superluminescent diode     

Analysis of metal-clad anti resonant reflecting optical waveguidefor polarizer applications

The dispersion and attenuation characteristics of an ARROW (antiresonant reflecting optical waveguide) with and without thin metal layers deposited on the outside of the interference cladding layer are investigated. These thin metal layers improve the polarization-selective performance of the ARROW considerably. A simple analytical expression to calculate the optimal thickness of the metal layer is derived     

Theoretical Studies of Polarization Bistability in Birefringent ARROW VCSELs

The polarization bistable characteristics of birefringent antiresonant reflection optical waveguide (ARROW) vertical-cavity surface-emitting lasers (VCSELs) under external optical injection is studied and juxtaposed theoretically with an equivalent index-guided device. The simulation results show that ARROW VCSELs exhibit bistable behaviour and have wider hytheresis loops. The wider hytheresis loop in ARROW VCSEL is attributed to the difference in the lateral profiles of the two polarization modes, resulting in the accentuation of the optical gain difference between the two polarizations. This is because the introduction of a birefringent ARROW has an equivalent effect of creating an anisotropic geometrical cavity in the laser structure. Our theoretical studies also show that the polarization bistability characteristics of ARROW VCSELS are not sensitive to small values of birefringence and can be easily tailored by varying the cladding thicknesses, an option that is not available to index-guided VCSELs     

Design of Stable Single-Mode Chaotic Light Source Using Antiresonant Reflecting Optical Waveguide Vertical-Cavity Surface-Emitting Lasers

The influence of external optical feedback (EOFB) on the lasing characteristics of 1.55-mum antiresonant reflecting optical waveguide (ARROW) vertical-cavity surface-emitting lasers (VCSELs) with various core radii are analyzed theoretically. It is found that ARROW VCSELs with large core radii (i.e., > 4 mum) respond more sensitively to EOFB than that with small core radii (i.e., les 4 mum). Furthermore, strong EOFB-driven ARROW VCSELs with large radii show more difficult to sustain single-mode chaotic oscillation than those with small radii. This is because radiation loss margin of ARROW reduces with the increase of core radii so that the presence of carrier spatial-hole burning deteriorates the stable single-mode operation of VCSELs. However, if the dimensions of ARROW as well as the radius of injection current aperture can be selected appropriately, stable single-mode chaotic light sources can be obtained from EOFB-driven ARROW VCSELs with large core radius.     

Analysis of N×N passive optical starcoupler based on the normal modes of N input waveguides

An integrated passive N×N optical star coupler on silicon wafer is described. Antiresonant reflecting optical waveguides (ARROWs) are analyzed and utilized as the input and output waveguides of the N×N coupler. Combining the exact solutions of the slab ARROW waveguide with the effective index method, a 5×5 coupler is analyzed. In the slab waveguide analysis, the input waveguides are coupled to their neighbors. The interaction of the waveguides is described in terms of the normal modes of propagation. The resultant field distribution is then diffracted into the free space region which separates the input and output sections. The radiation illuminates the receiving aperture from which the receiving N waveguides branch out, each output element obtaining equal power levels. Different types of loss such as spillover loss and mismatch loss were analyzed and estimated for N=5. A 5×5 star coupler with a transmission efficiency of 56% at a wavelength of 1.3 μm is achievable     

Photonic Crystal Slab Waveguides Based on Antiresonant Reflecting Optical Waveguide Structures

A novel two-dimensional photonic crystal slab waveguide based on an antiresonant reflecting optical waveguide (ARROW) structure is proposed and designed. Lightwaves propagating in this waveguide are confined by antiresonance reflection vertically and the photonic band gap laterally. In order to obtain the characteristics of the ARROW-based photonic crystal waveguides, the three-dimensional finite-difference time-domain simulations are performed. With a lateral adiabatic taper, a coupling efficiency of 80.3% from a single-mode fiber to the ARROW-based photonic crystal waveguide of a single-line defect is obtained. In addition, propagation losses less than 10 dB/mm and bend losses of 0.23 and 0.39 dB/bend for the designed 60$^{circ}$ and 120$^{circ}$ bends are achieved at an operating wavelength of $1.55~mu{hbox {m}}$.      

Suppression of polarization switching in birefringent antiresonant reflecting optical waveguide vertical-cavity surface-emitting lasers

Influence of birefringence on the multimode operation of antiresonant reflecting optical waveguide (ARROW) vertical-cavity surface-emitting lasers (VCSELs) is analyzed. It can be shown that polarization switching is mainly due to thermal lensing effects. Hence, a new design rule is proposed to optimize the dimensions of ARROW for the suppression of polarization switching. Using the optimized design, the maximum single-polarization output power of VCSELs can be tripled. In addition, it is shown that the performance of the optimized ARROW VCSELs will not be deteriorated by the uncertainty of birefringence.