- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
[IEEE 2018 IEEE 15th International Conference on Group IV Photonics (GFP) - Cancun (2018.8.29-2018.8.31)] 2018 IEEE 15th International Conference on Group IV Photonics (GFP) - Widely Tunable Ce:YIG on Si Microring Isolators for TE Mode Operation
摘要： We demonstrate fully integrated optical isolators using bonded Ce:YIG on silicon microrings with an integrated electromagnet. The isolator operates for TE mode input light and can be tuned between 1540 to 1580nm with >20dB isolation.
关键词： microring,isolator,silicon photonics
更新于2025-09-23 15:22:29
-
Bi substituted YIG ceramics isolator for optical communication
摘要： We have succeeded in synthesizing transparent (BixY3-x)Fe5O12 [x ? 0e1.1] ceramics by reactive sintering method for the ?rst time in the world. The transmission spectrum of Bi-doped YIG showed character-istics comparable to the Bi:Gd3Fe5O12 single crystal produced by LPE method. The obtained Bi:YIG ceramic was uniformly composed of grains around below 5 mm. Residual pores, secondary phases and grain boundary phases were not detected. The distribution of Bi, Y, and Fe in this material was extremely uniform for up to x ? 0.4, but a rather high concentration of Bi at grain boundaries was detected by HR-TEM-EDS analysis for x ? 0.8. The Faraday rotation angle linearly increased with the Bi content, and the Faraday rotation angle per atomic % of Bi was (cid:2)31.2 deg./cm at 1550 nm, and this value was similar to the (Bi1.1Gd1.9)Fe5O12 single crystal produced by LPE method. In addition to LPE method which requires a seed substrate (Gd3Ga5O12) and a steep temperature gradient, it was demonstrated in this work that Bi-doped iron garnet can be synthesized by solid-state reactive sintering method, and also con?rmed that the magneto-optical performance of the polycrystalline Bi:YIG ceramics was equivalent to single crystal.
关键词： Isolator,YIG ceramics,Bi-substituted,Faraday rotation,Transparent
更新于2025-09-16 10:30:52
-
[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Feedback Insensitive External-Cavity Semiconductor Ring Laser Utilizing a Weak Intracavity Isolator
摘要： External optical feedback (EOF), caused by the return loss of connected circuits, is well known to have a strong impact on the performance of semiconductor lasers [1]. Feedback effects are usually prevented by placing an optical isolator at the output of the laser. A strong isolation value of approximately 60dB is typically required for tunable lasers. It has proven difficult to implement sufficiently strong optical isolators in a form suited to photonic integration [2]. For this reason we have previously proposed a ring laser with weak intracavity isolation to enable a feedback insensitive integrated tunable laser [3]. In such a laser the isolator is used only to enforce unidirectional operation of the device and the returned signal couples in the lossy counter-propagating direction. Using our rate equation analysis it was predicted that 10dB intracavity isolation completely suppresses the effects of EOF over the operating range of interest in terms of output power, linewidth and relative intensity noise. In such a cavity, the weak isolation can now be implemented with known integration schemes [2]. In this contribution we demonstrate for the first time that insensitivity can indeed be achieved using a ring laser with weak intracavity optical isolation. The laser system is schematically shown in Fig. 1 and is implemented using polarization maintaining optical fiber, a multi-quantum well semiconductor optical amplifier and an optical isolator consisting of a free space Faraday rotator and two polarizers. By changing the orientation of the polarizers the amount of isolation can be set, allowing for a direct comparison to our theory. Finally, two 3dB fiber-fused splitters are used as output couplers to make the laser cavity as symmetrical as possible when no isolation is provided.
关键词： intracavity isolation,External optical feedback,optical isolator,ring laser,semiconductor lasers
更新于2025-09-12 10:27:22
-
Magneto-Optical Isolator Based on Ultra-Wideband Photonic Crystals Waveguide for 5G Communication System
摘要： This paper presents a novel magneto-optical isolator based on an ultra-wideband and high efficiency photonic crystals (PCs) waveguide and gyromagnetic ferrites. The three-dimensional numerical simulation finds that the photonic crystals waveguide’s (PCW) transmission efficiency rises with its height and width. The corresponding experiments are performed by using a triangular lattice Al2O3 dielectric posts array in 5G millimeter wave band. The measured transmission efficiency is up to 90.78% for the optimal PCs waveguide structure, which has ultra-wide operating bandwidth from 23.45 to 31.25 GHz. The magneto-optical isolator is designed by inserting two rectangular gyromagnetic ferrites into the PCs waveguide. Due to the contrast between the effective permeability of the left and right circular polarization waves passing through the magnetized ferrite sheets, the ferromagnetic resonance absorption of the forward and reverse waves is different. By using finite element method, the isolation is optimized to be 49.49 dB for the isolator and its relative bandwidth reaches 8.85%. The high isolation, broadband, and easy integration indicate that our designed magneto-optical isolator has significant advantage in 5G communication systems.
关键词： photonic crystals waveguides,magneto-photonic isolator,wideband,5G communication,photonic band gap
更新于2025-09-12 10:27:22
-
Nonreciprocal propagation in optical fibers
摘要： Nonreciprocal propagation in optical fibers presents practical interest. The present work treats the problem of nonreciprocal propagation in nonabsorbing cylindrically layered structures at axial magnetization characterized by magnetooptic electrical permittivity, ?ε, and magnetic permeability, ?μ, tensors, using transverse circularly polarized representation. The solutions to the vector Helmholtz equation are expressed analytically as functions of circular cylindrical coordinates (cid:37), ?, and z. The results are applied to a magnetooptic circular cylindrical waveguide and illustrated on fiber waveguides with an yttrium iron garnet (YIG) core and a cladding formed by gallium substituted yttrium iron garnet (GaYIG) at the optical communication wavelength of 1.55 μm. The propagation distance in the waveguide for a π/4 azimuth rotation of a transverse linearly polarized incident wave on the waveguide axis required in isolators is about 100 μm.
关键词： magneto-optical effect,Faraday effect,isolator,nonreciprocity
更新于2025-09-12 10:27:22
-
Design of high-performance and tunable magneto-optical isolators for He–Ne laser
摘要： Herein, we report on high-performance magnetophotonic crystal (MPC) structures, which can be adjusted to create perfect magneto-optical isolators (MOIs) for helium–neon lasers operating at a wavelength of 632.8 nm. The adjustment is carried out by tuning the applied magnetic field to use the high potential of the CeF3 as a new and transparent visible Faraday rotator. For practical purposes, to avoid instabilities due to wavelength fluctuations, we show that achieving a suitable tunable MOI with a flat-top response is possible when the appropriate MPC design is approached.
关键词： wavelength 632.8 nm,magneto-optical isolator,He–Ne laser,magnetic field tunability
更新于2025-09-11 14:15:04
-
[IEEE 2019 IEEE Avionics and Vehicle Fiber-Optics and Photonics Conference (AVFOP) - Arlington, VA, USA (2019.11.5-2019.11.6)] 2019 IEEE Avionics and Vehicle Fiber-Optics and Photonics Conference (AVFOP) - Magnetless Thin Film Waveguide Optical Isolators Based on Bi-Substituted Iron Garnet Material
摘要： Optical isolators based on magneto-optical materials have been demonstrated that exhibit less than 1 dB insertion loss and up to 20 dB isolation in the C-band wavelength range. Ridge waveguide Faraday rotators have been shown to exhibit more than 45° effective isolation in most of these films with insertion loss less than 1 dB. An important feature that has not received as much attention is the saturation magnetization of these films in most of these prototypes (22, 25, 27).
关键词： optical,isolator,waveguide,thin film,magnetless
更新于2025-09-11 14:15:04