Browsing by Author "Hsu, Yung"

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110 GHz hybrid mode-locked fiber laser with enhanced extinction ratio based on nonlinear silicon-on-insulator micro-ring-resonator (SOI MRR)
(2016-03)
Liu, Yang
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Hsu, Yung
;
Chow, Chi-Wai
;
Yang, Ling-Gang
;
Yeh, Chien-Hung
We propose and experimentally demonstrate a new 110 GHz high-repetition-rate hybrid mode-locked fiber laser using a silicon-on-insulator microring-resonator (SOI MRR) acting as the optical nonlinear element and optical comb filter simultaneously. By incorporating a phase modulator (PM) that is electrically driven at a fraction of the harmonic frequency, an enhanced extinction ratio (ER) of the optical pulses can be produced. The ER of the optical pulse train increases from 3 dB to 10 dB. As the PM is only electrically driven by the signal at a fraction of the harmonic frequency, in this case 22 GHz (110 GHz/5 GHz), a low bandwidth PM and driving circuit can be used. The mode-locked pulse width and the 3 dB spectral bandwidth of the proposed mode-locked fiber laser are measured, showing that the optical pulses are nearly transform limited. Moreover, stability evaluation for an hour is performed, showing that the proposed laser can achieve stable mode-locking without the need for optical feedback or any other stabilization mechanism.
192-Gbit/s PAM-4 Optical Interconnect using Mode-Division Multiplexing
(2018-01-01)
Hsu, Yung
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Wu, Xinru
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Chuang, Chun-Yen
;
Chow, Chi-Wai
;
Tsang, Hon Ki
192-Gbit/s pulse-amplitude-modulation-4 (PAM-4) signal transmission for on-chip optical interconnects using mode-division-multiplexing (MDM) is experimentally investigated. 3 channels are successfully mode multiplexed and de-multiplexed satisfying the forward-error correction (FEC) requirement.
2.6 Tbit/s On-Chip Optical Interconnect Supporting Mode-Division-Multiplexing and PAM-4 Signal
(2018-06-01)
Hsu, Yung
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Chuang, Chun-Yen
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Wu, Xinru
;
Chen, Guan-Hong
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Hsu, Chin-Wei
In this letter, we combine the use of dense-wavelength-division-multiplexing and mode-division-multiplexing (MDM) with advanced-modulation formats for on-chip optical interconnects. A three-mode MDM multiplexer (MUX) and de-multiplexer (DEMUX) was designed and used. Each wavelength carrier had an aggregate data rate of 192-Gbit/s using 4-level pulse-amplitude-modulation. The mode crosstalk of the MDM MUX/DEMUX was measured to he below -20 dB in the 40-nm wavelength band from 1520 to 1560 nm. Fourteen wavelength channels are multiplexed and successfully transmitted with an aggregate transmission capacity of 2.6 Tbit/s (14 wavelengths x 3 modes x 64 Gbit/s) with all channels satisfying the hard-decision forward-error-correction threshold. Numerical analysis of the mode crosstalk is also performed.
20 Gbit/s Tricolor R/G/B Laser Diode based Bi-directional Signal Remodulation Visible Light Communication System
(2018-01-01)
Wei, Liang-Yu
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Hsu, Chin-Wei
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Hsu, Yung
;
Chow, Chi-Wai
;
Yeh, Chien-Hung
We demonstrate a bi-directional signal-remodulated visible-light-communication (VLC) system using tricolor R/G/B laser diodes to produce a 20.231-Gbit/s orthogonal-frequency-division-multiplexed (OFDM) downstream signal and 2-Mbit/s remodulated on-off-keying (OOK) upstream signal.
512-Gbit/s PAM-4 Signals Direct-Detection using Silicon Photonics Receiver with Volterra Equalization
(2018-01-01)
Hsu, Yung
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Chuang, Chun-Yen
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Wei, Liang-Yu
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Chow, Chi-Wai
;
Wu, Xinru
A 400-Gbit/s Ethernet (GbE) pulse-amplitude-modulation-4 (PAM-4) over 10-km single-mode-fiber (SMF) transmission direct-detected by an integrated silicon-photonics-receiver satisfying the IEEE P802.3bs requirement; and its feasibility to support 512-Gbit/s were illustrated.
64-Gbit/s PAM-4 20-km Transmission Using Silicon Micro-ring Modulator for Optical Access Networks
(2017-01-01)
Hsu, Yung
;
Tzu, Ta-Ching
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Lin, Tien-Chien
;
Chung, Chun-Yen
;
Wu, Xinru
We demonstrate the feasibility of using silicon-micro-ring-modulators for 50-Gbitis and 64-Gbit/s pulse-amplitude-modulation-4 (PAM-4) communications in a 20-km single-mode fiber (SMF) link with Volterra-filtering. The integrated transmitter may be used in passive optical-access-networks with 20-kin-reach and 64-split-ratio.
Based on Silicon-micro-ring-resonator and Triple-ring Cavity for Stable and Tunable Erbium Fiber Laser
(2018-01-01)
Hsu, Yung
;
Chang, Yuan-Chia
;
Yeh, Chien-Hung
;
Chow, Chi-Wai
;
Chen, Jing-Heng
In this paper, a stable and wavelength-switchable erbium-doped fiber (EDF) laser by utilizing the silicon-micro-ring-resonator (SMRR) and multiple-fiber-ring (MFR) scheme is demonstrated. Here, three optical couplers (CPs) can construct the passive MFR in the proposed and achieve single-longitudinal-mode (SLM) output simultaneously. The SMRR is used inside a fiber cavity as mode restrict element for wavelength-tuning. By properly adjusting the polarization controllers (PCs), the output wavelength can be tuned in a wavelength range of 1544.35 to 1564.10nm with a similar to 2.0 nm tuning step. Hence, the proposed EDF laser can reach the characteristics of SLM output, 35 kHz output linewidth, and optical single-to-noise ratios (OSNRs) of > 54.9 dB. In addition, the output stabilities of the power and wavelength in the proposed EDF laser are also discussed.
Bi-directional Visible Light Communication Using a Single 682-nm Visible Vertical-Cavity Surface-Emitting Laser (VCSEL) and Signal Remodulation
(2017-01-01)
Wei, Liang-Yu
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Hsu, Chin-Wei
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Hsu, Yung
;
Yeh, Chien-Hung
;
Chow, Chi-Wai
We demonstrate a bi-directional signal-remodulated visible light communication (VLC), using 8.148-Gbit/s orthogonal-frequency-division-multiplexed (OFDM) downstream and signal remodulated 2-Mbit/s on-off-keying (OOK) upstream, with 3-m free-space transmission distance.
Compact 84 GHz passive mode-locked fiber laser using dual-fiber coupled fused-quartz microresonator
(2017-10-01)
Liu, Tze-An
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Hsu, Yung
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Chow, Chi-Wai
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Chuang, Yi-Chen
;
Ting, Wei-Jo
We propose and demonstrate a compact and portable-size 84-GHz passive mode-locked fiber laser, in which a dual-fiber coupled fused-quartz microresonator is employed as the intracavity optical comb filter as well as the optical nonlinear material for optical frequency comb generation. About eight coherent optical tones can be generated in the proposed fiber laser. The 20-dB bandwidth is larger than 588 GHz. The full-width halfmaximum pulse-width of the proposed laser is 2.5 ps. We also demonstrate the feasibility of using the proposed passive mode-locked fiber laser to carry a 5-Gbit/s on-off-keying signal and transmit over 20-km standard single mode fiber. A 7% forward error correction requirement can be achieved, showing the proposed fiber laser can be a potential candidate for fiber-wireless applications. (C) 2017 Society of Photo-Optical Instrumentation Engineers (SPIE)
Employment of silicon-micro-ring resonator and compound-ring architecture for stable and tunable single-longitudinal-mode fiber laser
(2018-09-01)
Hsu, Yung
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Yeh, Chien-Hung
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Cheng, Hao-Yun
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Chang, Yuan-Chia
;
Chow, Chi-Wai
In this work, a wavelength-switchable erbium-doped fiber (EDF) glasses-type compound-ring (GTCR) laser with stable single-longitudinal-mode (SLM) oscillation is proposed and presented. In the experiment, to accomplish wavelength-tunable operation, a silicon-micro-ring-resonator (SiMRR) is utilized inside the ring cavity, when the birefringent loss of EDF laser is adjusted properly. Moreover, the GTCR configuration is proposed to as the mode-filter for suppressing the multi-longitudinal-mode (MLM) to achieve the SLM oscillation. Here, the measured linewidth of output wavelength is 61 kHz. The output stabilities of the proposed SiMRR EDF compound-ring laser are also discussed experimentally. (C) 2018 Elsevier Ltd. All rights reserved.
Generating Radially and Azimuthally Polarized Beams by Using a Pair of Lateral Displacement Beamsplitters
(2016-09-01)
Han, Chien-Yuan
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Wei, Zhi-Hao
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Hsu, Yung
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Chen, Kun-Huang
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Yeh, Chien-Hung
This paper proposes a modified polarization converter for generating radially and azimuthally polarized beams. Based on a Mach-Zehnder-like interferometric structure, the device consists of a pair of lateral displacement beamsplitters (LDBs) and two half-wave plates that manipulate the states of polarization of incident linearly polarized light. Through the coherent superposition of two orthogonal Hermite-Gaussian modes in the far field, radially and azimuthally polarized beams can be obtained simultaneously. A prototype was assembled to demonstrate the feasibility of the design. The proposed design has the advantage of having a simple, symmetric, compact, and robust structure. In addition, the introduction of LDBs substantially reduces the cost of this device. Moreover, the design can be applied to a broadband pulsed laser with considerable potential in high-power applications.
Mode-locking S-band erbium fiber laser by employing alcohol-based saturable-absorber
(2017-11-01)
Hsu, Yung
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Yeh, Chien-Hung
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Chow, Chi-Wai
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光電工程學系
;
Department of Photonics
In this work, we investigate a passively mode-locked erbium-doped fiber (EDF) laser employing alcohol-based saturable absorber (SA) in S-band window for the first time. The operated S-band range is completed by using erbium-doped silica fiber with depressed cladding scheme and 980 nm pump laser to produce the gain extension effect in S-band. The alcohol is utilized to serve as the saturable absorber (SA) of the EDF laser, which is cost-effective and easily-prepared. Here, the pulse repetition rate and pulse duration of proposed EDF laser are 2.55 MHz and 13.2 ns, respectively, when the 980 nm pump laser is set at 455 mW. In addition, to the best of our knowledge, it is the first investigation of passively mode-locked EDF laser with an alcohol-based SA in S-band.
Narrow line-width single-longitudinal-mode fiber laser using silicon-on-insulator based micro-ring-resonator
(2016-02)
Liu, Yang
;
Hsu, Yung
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Hsu, Chin-Wei
;
Yang, Ling-Gang
;
Chow, Chi-Wai
In this work, we propose and demonstrate a stable single-longitudinal-mode (SLM) fiber laser with narrow line-width by using an integrated silicon-on-insulator micro-ring resonator (SOI MRR) and two subsidiary fiber rings for the first time, to the best of our knowledge. The laser is tunable over the wavelength range from 1546 to 1570 nm, with only step tuning of 2 nm steps. A maximum 49 dB side mode suppression ratio (SMSR) can be achieved. The compact SOI MRR provides a large free-spectral-range (FSR), while the subsidiary rings provide Vernier effect producing a single lasing mode. The FSR of the SOI MRR can be very large and controllable (since it is easy to fabricate small SOI MRR when compared with making small fiber-rings) using the complementary-metal-oxide-semiconductor (CMOS) compactable SOI fabrication processes. In our proposed laser, the measured single side-band (SSB) spectrum shows that the densely spaced longitudinal modes can be significantly suppressed to achieve SLM. The laser linewidth is only 3.5 kHz measured by using the self-heterodyne method. 30 min stability evaluation in terms of lasing wavelength and optical power is performed; showing the optical wavelength and power are both very stable, with fluctuations of only 0.02 nm and 0.8 dB, respectively.
Silicon-on-Insulator (SOI) based Polarization-Exchanger using Asymmetric Directional Coupler
(2018-01-01)
Peng, Ching-Wei
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Chang, Yuan-Chia
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Cheng, Ming-Wei
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Hsu, Yung
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Wei, Liang-Yu
We propose an silicon-on-insulator (SOI) based polarization-exchanger using bi-level-tapers and asymmetric-directional-couplers. Signal from transverse-electric (TE) polarization can be switched to transverse-magnetic (TM) polarization and vice versa. Crosstalk <= -25dB is observed in 40nm wavelength window.
Solution-Processed Vertical Organic Transistors Fabricated by Nanoimprint Lithography
(2013-02-01)
Wu, Yang-Kai
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Huang, Jian-Hao
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Tsai, Wu-Wei
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Chen, Yung-Pin
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Lin, Shih-Chieh
In this letter, we demonstrate the first vertical-channel organic transistor using nanoimprint technology to produce a base electrode with high-density nanometer pores to well control the channel current vertically flowing through the pores. The aspect ratios of nanopores, which determine the switching performance of the vertical transistor, are greatly enhanced by transferring the nanostructure to the underlying layers. Without pore accumulation, a low leakage current can be achieved. The vertical transistor delivers an ON current of 0.35 mA/cm(2) and an ON/OFF current ratio of around 3000 at 1.8 V. The results prove the feasibility to produce low-voltage organic transistors over a large area with potentially low production cost.
Stabilized single-longitudinal-mode erbium fibre laser employing silicon-micro-ring resonator and saturable absorber
(2018-07-01)
Hsu, Yung
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Yeh, Chien-Hung
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Chow, Chi-Wai
;
Chang, Yuan-Chia
;
Cheng, Hao-Yun
In the paper, a wavelength-tunable erbium-doped fiber (EDF) ring laser with stable single-longitudinal-mode (SLM) oscillation is proposed and investigated. Here, a silicon-microring-resonator can be applied in a laser cavity for tuning wavelength in the C-band range. To complete the SLM oscillation, an unpumped EDF-based saturable absorber is used to act as ultra-narrowband filter for suppressing other oscillation modes. Additionally, the output stabilities of power and wavelength in the proposed EDF ring laser are also executed and discussed.
Sub-100 nm ALD-assisted nanoimprint lithography for realizing vertical organic transistors with high ON/OFF ratio and high output current
(2014-12-01)
Hsu, Yung
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Fang, Xiang
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Wang, Lon A.
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Zan, Hsiao-Wen
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Meng, Hsin-Fei
We introduced a conformal atomic-layer-deposited aluminum oxide layer to cover the imprint mold to reduce the feature size and to strengthen the mold durability. A nano-hole array pattern with diameter down to 85 nm was successfully transferred to sample substrate to fabricate a vertical organic transistor. The Imprint vertical organic transistor exhibited high output current density as 4.35 cm(2)/V s and high ON/OFF current ratio as 11,000 at a low operation voltage as 1.5 V. (C) 2014 Elsevier B.V. All rights reserved.
Ten-channel mode-division-multiplexed silicon photonic integrated circuit with sharp bends
(2019-04-01)
Li, Chen-lei
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Jiang, Xiao-hui
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Hsu, Yung
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Chen, Guan-hong
;
Chow, Chi-wai
A multimode silicon photonic integrated circuit (PIC) comprising a pair of on-chip mode (de)multiplexers with 10-mode channels and a multimode bus waveguide with sharp bends is demonstrated to enable multi-channel on-chip transmissions. The core width of the multimode bus waveguide is chosen such that it can support 10 guided modes, of which there are four transverse-magnetic polarization modes and six transverse-electric polarization modes. This multimode bus waveguide comprises sharp bends based on modified Euler curves. Experimental results demonstrate that the present silicon PIC enables the 10-channel on-chip transmission with a low inter-mode crosstalk of approximately -20 dB over a broad bandwidth of 1520-1610 nm even when the bending radius of the S-bend is as small as 40 mu m. Compared with a silicon PIC using a conventional arc-bend with the same bending radius, our proposed PIC demonstrates a significant improvement.
Utilizing a silicon-photonic micro-ring-resonator and multi-ring scheme for wavelength-switchable erbium fiber laser in single-longitudinal-mode
(2016-06)
Yeh, Chien-Hung
;
Hsu, Yung
;
Chow, Chi-Wai
;
光電工程學系
;
Department of Photonics
In this paper, a stable and wavelength-switchable silicon-photonic erbium-doped fiber (EDF) triple-ring laser is proposed and demonstrated. In the experiment, the integration of a silicon-on-insulator (SOI)-based grating coupler and silicon-micro-ring-resonator (SMRR) are coupled and connected to the proposed EDF triple-ring laser for generating wavelength. Here, the output wavelength can be adjusted in a wavelength range of 1529.8 -1561.8 nm with a 2.0 nm tuning step according to the free spectrum range (FSR) of the SMRR. Moreover, the stability performance of the output power and wavelength are also discussed and analyzed.
Visible Light Communication Using Advertisement-Light-Board and Rolling-Shutter-Effect based CMOS Mobile-Phone Camera
(2018-01-01)
Shiu, Ruei-Jie
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Liu, Yen-Chun
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Chow, Chi-Wai
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Wei, Liang-Yu
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Hsu, Yung
We demonstrate a visible-light-communication (VLC) system using advertisement-light-board and CMOS-camera. Experiments at wireless transmission distances of 50cm, 100cm and 150cm are performed, and at data-rate of 720bit s, satisfying the forward-error-correction (FEC) threshold.