The Experts below are selected from a list of 7326 Experts worldwide ranked by ideXlab platform
Kin Seng Chiang - One of the best experts on this subject based on the ideXlab platform.
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Polarization‐insensitive Polymer Waveguide Bragg gratings
Microwave and Optical Technology Letters, 2020Co-Authors: Sin Yip Cheng, Kin Seng Chiang, Hau Ping ChanAbstract:We report the design and fabrication of Bragg gratings in benzocyclobutene (BCB) channel Waveguides with emphasis on the demonstration of their polarization dependence. The effects of the stress-induced birefringence in the Waveguide on the polarization dependence of the Bragg gratings are characterized and discussed. Our results show the possibility of realizing tunable polarization-insensitive Bragg-grating filters with simple Polymer Waveguide structures. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 334–338, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21342
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Buried graphene electrode heater for a Polymer Waveguide thermo-optic device
Optics Letters, 2019Co-Authors: Xibin Wang, Zeshan Chang, Kin Seng ChiangAbstract:We propose the use of graphene as the electrode heater material for a Polymer Waveguide thermo-optic (TO) device. Because a graphene electrode can be buried in a Polymer Waveguide without introducing a significant loss to the transverse magnetic polarized light, we can do away with the buffer layer that is required in a conventional TO device to isolate the metal electrode heater from the Waveguide and, hence, reduce the driving electric power of the device. To demonstrate the principle, we fabricate and compare two Polymer Waveguide TO mode switches based on the configuration of a balanced Mach–Zehnder interferometer, which are identical except that one uses a buried graphene electrode and the other uses an aluminum electrode deposited on the Waveguide surface. Our experimental device that uses a graphene electrode has a switching power almost four times lower and also responds faster. The use of buried graphene electrodes is an effective approach to reducing the power consumption of TO devices.
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All-Optical Control of Propagation Loss with a Graphene-Embedded Polymer Waveguide
2018 Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR), 2018Co-Authors: Zeshan Chang, Kin Seng ChiangAbstract:We demonstrate, theoretically and experimentally, all-optical control of propagation loss with a graphene-embedded Polymer Waveguide. Using a 10-mm long Waveguide, we achieve 4.6-dB loss modulation for 1550-nm light with 12.4-dBm co-propagating 980-nm pump light.
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Four-mode-selective photonic lantern based on two-layer Polymer Waveguide branches
2016 21st OptoElectronics and Communications Conference (OECC) held jointly with 2016 International Conference on Photonics in Switching (PS), 2016Co-Authors: Yunfei Wu, Kin Seng ChiangAbstract:We design and fabricate a four-core photonic lantern with two-layer asymmetric Polymer Waveguide branches to spatially (de)multiplex the LP01, LP11a, LP11b, and LP21a modes. The device operates over the C+L band with negligible polarization dependence.
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Mode (De)multiplexer Based on Polymer-Waveguide Asymmetric Y-Junction
2016 Asia Communications and Photonics Conference (ACP), 2016Co-Authors: Jing Feng, Kaixin Chen, Jie Yun Wu, Kin Seng ChiangAbstract:We design a Polymer-Waveguide asymmetric Y-junction for (de)multiplexing LP01 and LP11a modes. Our fabricated device shows the optimal demultiplexed crosstalk of -22.2 dB at 1560 nm and the 10-dB bandwidth of ~40 nm.
Sangyung Shin - One of the best experts on this subject based on the ideXlab platform.
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characteristics of Polymer Waveguide notch filters using thermooptic long period gratings
IEEE Journal of Selected Topics in Quantum Electronics, 2005Co-Authors: Minsuk Kwon, Sangyung ShinAbstract:We demonstrate experimentally the feasibility of a Polymer Waveguide notch filter using a thermooptic long-period grating. This notch filter consists of a channel Waveguide, a cladding surrounding the channel, and buffer layers sandwiching the cladding. Periodic heaters formed on the upper buffer layer induce a long-period grating thermooptically. Thus, they generate temporarily a resonance band of notch type in the transmission spectrum of the filter. Using thermocurable Polymers, we have fabricated notch filters 1 and 2 that have different cladding thicknesses. Experimental results demonstrate two features of the notch filters. One feature is dynamical controllability of the attenuation of a resonance band. For TE mode, the maximum attenuation of notch filters 1 and 2 increases from 0 to 27 dB as the power applied to notch filters 1 and 2 increases from 0 to 851 and 1170 mW, respectively. The other feature is controllability of the direction and magnitude of the center wavelength shift occurring when the attenuation is tuned. The shift property depends on the cladding thickness. The measured characteristics of notch filters 1 and 2 are qualitatively in good agreement with our theoretical analysis. Using this feature, we may implement the notch filter whose attenuation is adjustable without center wavelength shift. This Polymer Waveguide notch filter may be used to implement a compact filter whose spectrum is dynamically tailored.
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Polymer Waveguide notch filter using two stacked thermooptic long-period gratings
IEEE Photonics Technology Letters, 2005Co-Authors: Minsuk Kwon, Sangyung ShinAbstract:A Polymer Waveguide notch filter using two stacked thermooptic long-period gratings is proposed. It is a long-period Waveguide grating whose transmission spectrum can be dynamically controlled. Thermooptic index perturbation, i.e., grating is temporarily induced by two groups of periodic heaters stacked vertically on the filter surface. The periods of the two groups are determined such that two different resonance bands are generated in the spectrum by the respective groups. Thus, the overall spectrum may be actively shaped by controlling the individual power applied to the two groups. Its feasibility is demonstrated experimentally by fabricating it with thermocurable Polymers.
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Tunable Polymer Waveguide notch filter using a thermooptic long-period grating
IEEE Photonics Technology Letters, 2005Co-Authors: Minsuk Kwon, Sangyung ShinAbstract:The feasibility of a Polymer Waveguide notch filter using a thermooptic long-period grating is demonstrated experimentally. It consists of a channel Waveguide, a cladding surrounding the channel, and buffer layers sandwiching the cladding. Periodic heaters, placed on the filter surface, induce thermooptically a long-period grating. The attenuation of the filter is controlled by adjusting the power applied to the periodic heaters. The filter is made of thermocurable Polymers by using conventional processes. For transverse-electric mode, its attenuation increases from 0 to 27 dB as the power applied to the periodic heaters increases from 0 to 851 mW. For the maximum attenuation spectrum, the 3-dB bandwidth of the attenuation band is 16 nm.
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TE-TM mode converter in a poled-Polymer Waveguide
IEEE Journal of Quantum Electronics, 1996Co-Authors: Wol-yon Hwang, Min-cheol Oh, Taehyoung Zyung, Sangyung ShinAbstract:A novel active TE-TM mode converter in a poled electrooptic Polymer Waveguide is demonstrated. The mode converter utilizes a 45/spl deg/-off poling configuration, which can be obtained by arranging upper- and lower-stripe poling electrodes with a proper lateral displacement. The mode-conversion properties and electrooptic effect are demonstrated by using a vector-beam propagation method in a buried channel-type Waveguide. Applications to integrated Polymer-Waveguide devices are also suggested.
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Explicit vector beam propagation method for uniaxial poled Polymer Waveguide devices
Proceedings of LEOS'94, 1994Co-Authors: Min-cheol Oh, Sangyung Shin, Wol-yon HwangAbstract:For the design and the analysis of integrated optic devices, the beam propagation method (BPM) has been widely used. A vectorial BPM (VBPM) was also developed to simulate the polarization effects and to analyze Waveguide structures having large index discontinuities. Recently, the VBPM was extended to treat anisotropic medium by taking the tensorial character of the dielectric constant /spl epsiv/ into account. However, this method using implicit numerical analysis is very complex and needs long computing time. To handle three-dimensional uniaxial Waveguide devices that consist especially of a poled electro-optic (EO) Polymer Waveguide, we developed a new VBPM based on an explicit finite difference (EFD) algorithm. This method is straightforward and easy to program. A novel polarization converter that may be implemented by appropriate poling of the EO Polymer Waveguide is also proposed and analyzed.
Hau Ping Chan - One of the best experts on this subject based on the ideXlab platform.
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Polarization‐insensitive Polymer Waveguide Bragg gratings
Microwave and Optical Technology Letters, 2020Co-Authors: Sin Yip Cheng, Kin Seng Chiang, Hau Ping ChanAbstract:We report the design and fabrication of Bragg gratings in benzocyclobutene (BCB) channel Waveguides with emphasis on the demonstration of their polarization dependence. The effects of the stress-induced birefringence in the Waveguide on the polarization dependence of the Bragg gratings are characterized and discussed. Our results show the possibility of realizing tunable polarization-insensitive Bragg-grating filters with simple Polymer Waveguide structures. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 334–338, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21342
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Bottom-Heating Approach for the Realization of Thermooptic Polymer Waveguide Devices
IEEE Photonics Technology Letters, 2011Co-Authors: Kin Seng Chiang, Hau Ping ChanAbstract:We propose a bottom-heating approach to realizing a thermo-optically tunable Polymer Waveguide device, where the electrode heater is deposited at the bottom of the Waveguide through a hole-etched substrate. Compared with the conventional top-heating approach, the bottom-heating approach can provide more effective optical isolation from the electrode, reduce the risk of damaging the Polymer material in the fabrication process, and simplify electric wiring. We demonstrate the idea experimentally with an ultraviolet written long-period grating on a Polymer Waveguide fabricated by an imprinting technique, which incorporates a bottom electrode heater for phase-shift tuning. The grating requires an electric power of 1.74 mW to produce a -phase shift.
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Broadband Multiport Dynamic Optical Power Distributor Based on Thermooptic Polymer Waveguide Vertical Couplers
IEEE Photonics Technology Letters, 2008Co-Authors: Kaixin Chen, Kin Seng Chiang, Hau Ping ChanAbstract:We propose a broadband multiport dynamic optical power distributor, which consists of a series of asymmetric vertical optical Waveguide directional couplers with thermooptically tunable splitting ratios. To demonstrate the idea experimentally, we fabricated a five-port optical power distributor with four Polymer Waveguide vertical couplers. The fabricated device is 9 mm long and allows a practically arbitrary optical power distribution to be achieved with a maximum electric power consumption less than 50 mW in any of the couplers and a response time of ~1 ms. The device operates effectively in the whole C-band without significant variations in performance.
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Polymer-Waveguide-based vertical coupler
Optics Communications, 2006Co-Authors: Z.j. Cheng, Hau Ping Chan, Z.l. Peng, K.x. Chen, Chongxiu YuAbstract:Abstract A 2 × 2 Polymer-Waveguide-based vertical coupler was designed and fabricated. The relationships between the coupling efficiency and the key optical design parameters of vertical coupler (such as the crossing angle, gap thickness between two Waveguide layers and the Waveguide dimensions) were investigated by using beam propagation method. Based on these simulations, a fully Polymer vertical coupler was demonstrated.
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Polarization dependence in Polymer Waveguide directional couplers
IEEE Photonics Technology Letters, 2005Co-Authors: Sin Yip Cheng, Kin Seng Chiang, Hau Ping ChanAbstract:We designed and fabricated benzocyclobutene-based Polymer Waveguide directional couplers and measured the polarization dependence of their splitting ratios. Wide-band polarization-insensitive operation and the possibility of using thermal tuning to maintain low polarization dependence were demonstrated.
Min-cheol Oh - One of the best experts on this subject based on the ideXlab platform.
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Polymer Waveguide birefringence modulators for polarization controllers
2012 17th Opto-Electronics and Communications Conference, 2012Co-Authors: Su-hyun Park, Min-cheol OhAbstract:A birefringence modulator for controlling the phase retardation between TE and TM polarizations is demonstrated using a Polymer Waveguide. Highly birefringent Polymer material is incorporated to increase the polarization dependence of the thermo-optic (TO) effect.
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Near Infrared external cavity tunable laser based on Polymer Waveguide Bragg gratings
2012 17th Opto-Electronics and Communications Conference, 2012Co-Authors: Beom-jun Cheon, Min-cheol OhAbstract:Wavelength tunable lasers operating at NIR wavelength is demonstrated by incorporating Polymer Waveguide Bragg reflectors. The external feedback laser Bragg grating exhibits single mode lasing. The wavelength tuning over 21 nm is demonstrated.
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near infrared tunable lasers with Polymer Waveguide bragg gratings
Optics Express, 2012Co-Authors: Min-cheol OhAbstract:Wavelength tunable lasers operating at near infrared (NIR) wavelength are demonstrated through the thermo-optic (TO) refractive index tuning of Polymer Waveguide Bragg reflectors. The Polymer-Waveguide device has superior TO efficiency for substantially changing the refractive index, and it enables direct tuning of the Bragg reflection wavelength over a wide range. The Waveguide is optimized for NIR wavelengths, and a third-order Bragg reflector is incorporated for facilitating fabrication of the grating. The laser exhibits an output power of 0 dBm, a side-mode suppression ratio of 40 dB, and a tuning range of 21 nm.
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Polymer Waveguide thermo optic switches with 70 db optical crosstalk
Optics Communications, 2006Co-Authors: Min-cheol OhAbstract:Abstract To reduce the crosstalk of the Polymer Waveguide optical switches, Waveguide attenuators are integrated with the switch on the same substrate. The switch and attenuator shares a single connected electrode which is controlled by a single current source. Due to the simple structure of the integrated attenuator, the device length is reduced to 10 mm so as to provide low insertion loss of 0.8 and 1.1 dB for 1300 and 1550 nm, respectively. Further radiation of the remained optical signal on the switch-off branch is induced by the integrated attenuator so that the switching crosstalk is reduced to −70 dB with an applied electrical power of 200 mW. The low crosstalk is maintained for the environmental temperature range of −10 to 55 °C.
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Thermooptic tunable wavelength filters using Polymer Waveguide Bragg gratings
Conference Proceedings. LEOS'98. 11th Annual Meeting. IEEE Lasers and Electro-Optics Society 1998 Annual Meeting (Cat. No.98CH36243), 1998Co-Authors: Min-cheol OhAbstract:We demonstrate a tunable wavelength optical Waveguide filter with a Bragg grating on a low-loss Polymer Waveguide. To control the peak wavelength of the Bragg reflector, an electrical power is applied to the device electrode so that the effective index of the Polymer Waveguide is change by the joule heating.
Kaixin Chen - One of the best experts on this subject based on the ideXlab platform.
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Band-Rejection Filter Based on Cascaded Two Sidewall Gratings in Multimode Polymer Waveguide
2019 Asia Communications and Photonics Conference (ACP), 2019Co-Authors: Lingfang Wang, Kaixin ChenAbstract:A simple band-rejection filter based on cascaded long period gratings in Polymer Waveguide is designed and demonstrated. Our fabricated device shows a maximum extinction ratio of ~19 dB around 1555 nm.
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Thermally-induced long-period grating mode converter on tapered Polymer Waveguide
2018 Asia Communications and Photonics Conference (ACP), 2018Co-Authors: Bo Wu, Wei Ke Zhao, Kaixin ChenAbstract:A thermally-induced long-period grating on tapered Polymer Waveguide is designed and fabricated for realizing a broadband reconfigurable LP01-LP11a mode conversion. Our fabricated device shows a 10-dB bandwidth over the entire C+L band and with a maximum conversion efficiency of 99.99% at 1529.55 nm.
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Mode (De)multiplexer Based on Polymer-Waveguide Asymmetric Y-Junction
2016 Asia Communications and Photonics Conference (ACP), 2016Co-Authors: Jing Feng, Kaixin Chen, Jie Yun Wu, Kin Seng ChiangAbstract:We design a Polymer-Waveguide asymmetric Y-junction for (de)multiplexing LP01 and LP11a modes. Our fabricated device shows the optimal demultiplexed crosstalk of -22.2 dB at 1560 nm and the 10-dB bandwidth of ~40 nm.
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Widely Wavelength-Tunable Mode Converter Based on Polymer Waveguide Grating
IEEE Photonics Technology Letters, 2015Co-Authors: Yubo Yang, Kaixin Chen, Kin Seng ChiangAbstract:We design and fabricate a corrugated grating on a Polymer Waveguide for the realization of the conversion between the fundamental mode and the higher order mode. The transmission characteristics of the device are insensitive to the polarization state of the input light. Our typical fabricated device shows a mode conversion efficiency higher than 99% over a bandwidth of ~4 nm and a temperature sensitivity of 3.5 nm/°C, which allows the operation wavelength of the device to be tuned over the C + L band with a temperature control <;30 °C. This mode converter could be integrated with other Waveguide devices to realize more sophisticated functions for mode-division-multiplexing systems.
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Widely Wavelength-Tunable Mode Converter Based on Polymer Waveguide Grating
IEEE Photonics Technology Letters, 2015Co-Authors: Yu Yang, Kaixin Chen, Kin Seng ChiangAbstract:We design and fabricate a corrugated grating on a Polymer Waveguide for the realization of the conversion between the fundamental mode and the higher order mode. The transmission characteristics of the device are insensitive to the polarization state of the input light. Our typical fabricated device shows a mode conversion efficiency higher than 99% over a bandwidth of ~4 nm and a temperature sensitivity of 3.5 nm/°C, which allows the operation wavelength of the device to be tuned over the C + L band with a temperature control