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John E Bowers - One of the best experts on this subject based on the ideXlab platform.

  • novel ultra short and ultra broadband polarization beam splitter based on a bent Directional Coupler
    Optics Express, 2011
    Co-Authors: John E Bowers
    Abstract:

    A novel ultra-short polarization beam splitter (PBS) based on a bent Directional Coupler is proposed by utilizing the evanescent coupling between two bent optical waveguides with different core widths. For the bent Directional Coupler, there is a significant phase-mismatch for TE polarization while the phase-matching condition is satisfied for TM polarization. Therefore, the TM polarized light can be coupled from the narrow input waveguide to the adjacent wide waveguide while the TE polarization goes through the coupling region without significant coupling. An ultra-short ( 10dB.

  • ultrashort broadband polarization beam splitter based on an asymmetrical Directional Coupler
    Optics Letters, 2011
    Co-Authors: Zhi Wang, John E Bowers
    Abstract:

    An ultrashort polarization beam splitter (PBS) based on an asymmetrical Directional Coupler is proposed by utilizing the evanescent coupling between a strip-nanowire and a nanoslot waveguide. In order to be convenient for integration with other components, mode converters between the nanoslot waveguide and the strip-nanowire are introduced and merged into S-bends to achieve an ultracompact PBS. As an example a 6.9 μm long PBS based on a silicon-on-insulator platform is designed, and the length of the coupling region is as small as 1.3 μm. Numerical simulations show that the present PBS has a very broad band (>160 nm) for an extinction ratio of >10 dB.

Senkuei Hsu - One of the best experts on this subject based on the ideXlab platform.

  • a novel compact forward wave Directional Coupler design using periodical patterned ground structure
    IEEE Transactions on Microwave Theory and Techniques, 2011
    Co-Authors: Senkuei Hsu, Juichih Yen
    Abstract:

    A novel forward-wave Directional Coupler with periodical patterned ground structures is proposed. The input impedance of the even and odd mode of the proposed Coupler can be matched, and the phase difference between the even and odd mode is also strongly enhanced. The equivalent models are constructed to predict the propagation properties based on the Bloch-Floquet theorem. A completed design procedure is also proposed based on the equivalent models. This two-layer structure is fabricated on Duroid substrate. 0.5-dB coupling level can be measured at 1.5 GHz, and the Coupler length is 0.5 λg. Compared to previous studies, the proposed Coupler can be designed at a lower frequency range with a smaller size.

  • a novel miniaturized forward wave Directional Coupler with periodical mushroom shaped ground plane
    IEEE Transactions on Microwave Theory and Techniques, 2010
    Co-Authors: Senkuei Hsu, Chunghao Tsai
    Abstract:

    A novel miniaturized forward-wave Directional Coupler with periodical mushroom-shaped ground plane is proposed. The Coupler can be designed with identical characteristic impedances for even and odd mode and enhanced the difference of propagation constants between the even and odd mode. These distinct propagation characteristics can be predicted by the equivalent-circuit model of a unit-cell using the Bloch-Floquet theorem. A tested sample is designed and fabricated on the FR4 substrate. We designed a 0-dB Coupler with the length about 1.28 λg, and 1.0-dB coupling is measured at 2.9 GHz due to the loss. Compared with previously studies, the proposed Coupler can be implemented to attain the highest coupling level with a smaller size.

Nuraini Elis - One of the best experts on this subject based on the ideXlab platform.

  • STUDI AWAL FABRIKASI DAN KARAKTERISASI Directional Coupler KONFIGURASI 4x4 SERAT OPTIK PLASTIK STEP INDEX MULTIMODE TIPE FD-620-10 MENGGUNAKAN METODE HEATING AND PRESSING
    2017
    Co-Authors: Nuraini Elis
    Abstract:

    Fabrikasi Directional Coupler singlemode maupun multimode berbentuk pandu gelombang slab masih sangat sulit dilakukan dan membutuhkan peralatan yang rumit. Untuk mengatasi kendala tersebut telah dilakukan fabrikasi Directional Coupler dengan metode Fused Biconical Tapered (FBT), yaitu dengan menggabungkan sejumlah serat optik pada panjang kopling tertentu sehingga menjadi Directional Coupler dengan N-port (Sekartedjo dkk, 2007). Metode yang digunakanpun cukup sederhana yaitu dengan membagi daya (power divider) pada Directional Coupler. Akan tetapi, pada metode Fused Biconical Tapered (FBT) masih ditemui beberapa kendala yaitu, adanya daya yang bocor melalui celah-celah benang pada saat penggandengan serat optik, sehingga daya yang dihasilkan tidak terbagi secara merata. Oleh karena itu, dalam penelitian ini Directional Coupler difabrikasi menggunakan bahan serat optik plastik (POF) step index multimode tipe FD-620-10 dengan metode Heating and Pressing ================================================================================================================ Fabrication Directional Coupler singlemode or multimode shaped slab waveguide is still very difficult to do and requires complex equipment. To overcome these obstacles has been done by the method of fabricating Directional Coupler Fused biconical Tapered (FBT), by combining a number of optical fibers in a particular coupling length so that a Directional Coupler with N-port (Sekartedjo et al, 2007). Digunakanpun fairly simple method is to divide the power (power divider) in the Directional Coupler. However, the method Fused biconical Tapered (FBT) is still encountered some constraints, namely, their power is leaking through the cracks thread when coupling the optical fiber, so that the generated power is not divided evenly. Therefore, in this study Directional Coupler fabricated using plastic optical fiber (POF) step index multimode type FD-620-10 with methods Heating and Pressin

J Marti - One of the best experts on this subject based on the ideXlab platform.

  • all optical switching structure based on a photonic crystal Directional Coupler
    Optics Express, 2004
    Co-Authors: F Cuestasoto, Alejandro Martinez, J Garcia, F Ramos, P Sanchis, Javie Lasco, J Marti
    Abstract:

    A novel all-optical switching structure based on a photonic crystal Directional Coupler is proposed and analyzed. Efficient optical switching is achieved by modifying the refractive index of the coupling region between the coupled waveguides by means of an optical control signal that is confined in the central region. Small length (around 1.1 mm) and low optical power consumption (over 1.5 W) are the main features estimated for this switching structure.

Zhiping Zhou - One of the best experts on this subject based on the ideXlab platform.

  • subwavelength grating assisted broadband polarization independent Directional Coupler
    Optics Letters, 2016
    Co-Authors: Lu Liu, Qingzhong Deng, Zhiping Zhou
    Abstract:

    This Letter presents both numerical and experimental results of a polarization-independent Directional Coupler based on slot waveguides with a subwavelength grating. The measured coupling efficiency is 97.4% for TE and 96.7% for TM polarization at a wavelength of 1550 nm. Further analysis shows that the proposed subwavelength grating Directional Coupler has a fabrication tolerance of ±20  nm for the grating structure and that the coupling efficiencies for the two polarizations are both higher than −0.5  dB (∼89%), exceeding the entire C-band (1525–1570 nm) experimentally.