Sökresultat - Ping Shum

In this paper, in order to achieve low differential mode group delay (DMGD) over the C+L band, we propose the hole-assisted graded-index few mode fiber (FMF) design supporting four nondegenerated linear polarized (LP) modes for a mode division multiplexing system. In order to determine th...

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Physics phenomena of multipulse compounds have enriched the life of ultrashort pulses beyond traditional pulse singlets in passively mode-locked fiber lasers. By developing a near zero-dispersion fiber laser, we report on the generation of dispersion-managed soliton (DMS) molecules. During propagati...

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In this article, we report robust vector soliton bunches arising in a passively mode-locked fiber laser based on carbon nanotube (CNT). By introducing a polarization-route-assisted module (PRAM) and finely adjusting the cavity birefringence, the soliton bunches can be flexibly manipulated to operate...

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In this paper, we propose a photonic crystal fiber with broadband ultra-flattened normal dispersion at 2 μm. In this fiber, a subwavelength air hole in the core region and air holes arrangement in the cladding region are used to control the property of dispersion. Wi...

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A secure key distribution scheme for orthogonal frequency division multiplexing (OFDM) passive optical network system is proposed and experimentally demonstrated. The training symbol (TS), which is used for time synchronization and channel estimation, is formed by adopting a noise-like chaotic seque...

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A bidirectional transmission and massive multi-input multi-output (MIMO) enabled radio over a multicore fiber system with centralized optical carrier delivery is experimentally investigated in this paper. Optical carriers for upstream are delivered from the central office to the remote antenna unit...

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Theoretical investigation on the mechanism of temporal depolarization effect in a polarization optical time-domain reflectometry (POTDR) system is conducted. First, the relationship between the dynamic range of the incomplete POTDR system and the degree of polarization (DOP) of the backscattered opt...

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The performance of conventional gas sensors based on light absorption in the mid-infrared are limited by the high-cost and low efficiency of photon detection at these wavelengths. In this paper, cascaded suspended waveguides are proposed and analyzed for mid-infrared gas sensing with enhanced detect...

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Recent research on nonlinear multimode interference (NL-MMI) based mode-locking method provides a new approach for ultrafast all-fiber lasers. Here, we report on the polarization dynamics of group velocity locked vector solitons (GVLVSs) and noise-like vector pulses (NLVPs) in a graded-index multimo...

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We report a novel low-loss splicing approach for hollow-core photonic crystal fiber (HC-PCF) and conventional single mode fiber (SMF) by inserting an etched SMF tip into the hollow core. If the divergence solid angle (DSA) of the inserted fiber tip is smaller than the guiding solid angle (GSA) of HC...

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We demonstrate an ultra-dense wavelength-division-multiplexing (UDWDM) passive optical network (PON) in a spatial-division-multiplexing system utilizing our home-made seven-core multicore fiber (MCF) with a self-homodyne coherent detection (SHCD) scheme. In the SHCD system, we transmit 12 channels o...

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We present an optically coupled chaotic system involving three-phase modulated electro-optic nonlinear loops and an optical coupler. The dynamical properties and the time delay signature (TDS) suppressing performance of the system is analyzed in detail. Numerical results show that the TDS can be sup...

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We propose and demonstrate a novel spatial-division multiplexed Mach–Zehnder interferometer (MZI) structure in heterogeneous multicore fiber (MCF) for simultaneous measurement of temperature and strain. The MZI structure is constituted of dual-tapered regions along heterogeneous MCF by us...

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