Originating from the emerging and intensively research of graphene, there have been tremendous improvements in the area of two dimensional materials (2D) based photonics. Its unique optoelectronics characteristics and the capability of being easily stacking to multilayer heterostructures have been proved to be able to generate some novel and distinctive optoelectronic devices, such as transparent conductive films, polarizers, saturable absorbers, optical modulators, photodetectors, and so on. Recently, we have experimentally found that beyond graphene, other two-dimensional layered materials such as topological insulators, MoS2 etc. also possess wideband nonlinear optics response using Z-scan measuring technique. By using the lager two or three order nonlinear properties, we have successfully demonstrated optical modulators, wavelength converter, polarizer and so on. And By using the saturable absorption property of these 2-D materials, different types of optical saturable absorber devices have been developed for the passive mode locking, passive Q-switching or single longitudinal mode of lasers. We can conclude that it is more flexible in manufacturing desirable and given photonics devices, and the performance of novle photonics devices can also be greatly boosted. It is expected that the research of two-dimensional nano-materials photonics will be developed predominantly in optoelectronic devices applications

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The generation of double-peaked laser spectral compression is demonstrated using a dispersion-increasing fiber (DIF). The experimental results are in excellent agreement as compared to numerical calculations.

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Bunched soliton formation and evolution in the polarizer- and absorber-free erbium-doped fiber laser is investigated. Even a weak polarization dependent loss can enable the passive mode-locking and vary its order from fundamental to harmonic condition, while the soliton forms are evolved into bunched state by simply enlarging the net gain.

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An all-fiber, all-normal-dispersion, polarization –APM passive mode-locked Yb-doped fiber laser is experimentally demonstrated at the 1um wavelength. With an external grating pairs for linear pulse-width compression, the final pulse-width can be as short as 693fs.

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The bound state of multiple soliton were experimentally demonstrated from a passive mode-locked Yb-doped fiber laser based on the nonlinear polarization mechanism at net normal dispersion region through adjustment of the waveplate. After pulse compression by the external grating pairs, the compressed bound pulses below 1 ps were successfully demonstrated.

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Optically pumped middle infrared (Mid-IR) dual wavelength lasers operated at room temperature were demonstrated. Two kinds of InGaAsSb/AlGaAsSb quantum well (QW) with different compositions, which were separated by a thin carrier blocking layer, were grown as active region in a single waveguide laser structure. Dual wavelength at 2.31m and 2.61m were lasing simultaneously when the optically injection is slight higher than the threshold condition.

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The authors demonstrate the transistor cut-off frequency and the base transit time of the LET from 25℃ to 55℃. The cut-off frequency increases and the base transit time decreases with increasing temperature due to the thermionic emission lifetime of quantum-wells at high temperature.

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We report a tunable pulsed optical parametric oscillator using a double-prism domain PPLN as simultaneously an electro-optic Q-switch and a parametric generator in a Nd:YVO4 laser. >2.3-kW peak-power eye-safe light was obtained with this system.

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Broadband terahertz (THz) Emission by two-color laser-induced filament in isotropic media, air and fused silica, are studied by the simulation of transient photocurrent model and experiments. The dependence between several parameters and the THz signal has been checked. The results of air and fused silica are compared and discussed.

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We observed the coherent effect of two kinds of nonlinear frequency conversion process. The fundamental beam (1064nm) and second harmonic beam (532nm) are used to generate the two processes in our simulation. We perform the simulation of frequency conversion by tightly focused Gaussian beam.

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In this work, a light source for high resolution optical coherence tomography system was designed, constructed and studied. The center wavelength of the generated supercontinuum is 1060 nm and the FWHM of the output spectrum can exceed 320 nm. We set up a free space Michelson interferometer with both axial and lateral scanning schemes as a prototype time-domain optical coherence tomography system. The experimentally measured point spread function indicates an axial resolution of <2 μm as compared to a theoretical resolution of <1.6 μm.

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To improve the performance of GaN-based VCSEL, AlGaN/GaN multiple quantum barrier is used to replace the conventional bulk AlGaN electron blocking layer. The laser output power shows significant improvement due to effective electron blocking ability resulted from multiple quantum barrier. This result is also observed by simulating the corresponding structure.

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Malignant neoplasm is the leading cause of death for 30 years in a row in Taiwan. Tumor angiogenesis is a critical factor in the growth and metastasis of most malignant neoplasms and cancer cell is considered to be associated with chemo- and radio-resistance that lead to the failure of therapies. More and more reports have shown that cancer cells can promote tumor angiogenesis and maintain their differentiation with the help of endothelium cells [1]. However, the dynamic interplay between the tumor angiogenesis environment and the growth of cancer cells in vivo is yet a complex unresolved subject. The purpose of this study is to time-course investigate the biology of cancer cells in vivo in the context of tumor angiogenesis. The mCherry regulatory melanoma stable cells were implanted into C57BL/6-c2J mice ears and were in vivo monitored by nonlinear optical microscopy. In order to study the relationship between tumor sizes and vessel permeability, we track the tumor growth in mice and inject the 150-kDa (the radius is about 8 nm) dextran labeled with fluorescein in the different tumor stages to examine the vessel permeability. The result demonstrates that the vessels permeability rate will increase with tumor size.

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We analyze a hybrid plasmonic nanocavity containing a silicon grating NW near a metal surface with a gain gap between. For such cavity with a short cavity length at wavelength λ = 1550 nm, a high quality factor near 550 and ultrasmall modal volume lower than 0.0019 (λ/n)3 are achievable.

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We consider nonresonatly-pumped excitonpolariton condensates in 1-D periodic potential. By analyzing the band structure of the system, we found that gap solitons form at the edge of the Brillouin zones when pumped nonuniformly.

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Dynamical characteristics of semiconductor lasers subject to both optoelectronic feedback and optical feedback are investigated by numerical simulation. The electrical power spectrum of individual system with undesired side peaks resulted from corresponding frequency of the delay loop can be eliminated by the applying another system with different time delay. Furthermore, under proper adjustment of the loop delay time, the main frequencies of power spectrum are changed correspondingly.

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Composition ratio detuned nonstoichiometric Si1-xGex saturable absorber for generating the passively mode-locked fiber laser is investigated. The Si1-xGex film with less Ge concentration possesses less optical absorption, which can reduce the mode-locking threshold to produce the passively mode-locked erbium-doped fiber laser with a pulsewidth of 340 fs.

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Demonstration of the active region in the resonant cavity (Resonant Cavity LET) is proposed in this paper. In order to enhance the FWHM and bandwidth of the RCLET, extra 8 pairs of TiO2/SiO2 DBRs are deposited. As a consequence, the optical confinement and spontaneous recombination lifetime is enhanced by Purcell effect.

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We experimentally generate crescent wave on the surface of vertical cavity surface emitting laser (VCSEL). The corresponding lasing characteristics including near/far field are also verified. Our results provide a special method to study optical surface waves.

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We demonstrate using polarization-gating cross-correlation frequency-resolved optical gating (PG-XFROG) to characterize ultrafast pulses with an octave-spanning continuous spectrum.

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A new approach for supercontinuum generation in solid media has been demonstrated that expands the spectrum from 450 nm to 980 nm at the -20 dB intensity level, with conversion efficiency of 54%. The pulse is verified to be phase coherent and could be compressed to a few femtosecond isolated pulse by FROG and spectral interferometric measurements.

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In this work, we experimentally demonstrate an environmentally stable 10 GHz ps hybrid FM mode-locked Er-doped fiber soliton laser that can produce stable single and bound soliton pulse trains with a sigma-type fiber cavity configuration.

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Relationship among output waveforms and maintaining stability for self-pulsating two-section distributed feedback laser is analyzed under different laser structure factors: cavity length, line-width enhancement factor, and facet phase shift. The oscillation stability analysis criteria are also discussed different to the existed papers.

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By experimental measurement and theoretical analysis, we demonstrate the control of modulation instability in nonlinear media. Appearance and suppression of modulation are observed in a series of spontaneous optical patterns as the intensity of input coherent beam increases, with different bias voltages and different background field intensity.

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By tilting the angle of dipole-dipole interaction with respect to the confined Bose-Einstein condensate trapped in a two-dimensional (2D) potential, we reveal the possibility to stabilize a 2D soliton by suppressing the Townes soliton instability. Due to the long-ranged and anisotropic interaction, it is the non-definite positive spectrum, which compensates the instability induced by the short-ranged nonlinearity.

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The design of a stable constant current source by using MOSFET as the current control device for driving the semiconductor laser diode is described. Adopting high precision and low temperature shift of circuit element, the short term stability of driver current source can reach 6.87×10^-6 .This high stability current driver for semiconductor laser diode satisfies interferometry application.

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Silicon quantum dots (Si-QDs) are attractive for many promising applications in silicon photonics. This paper presents a controlled synthesis of amorphous Si QDs (a-Si QDs) embedded in Si-rich SiOx (SRO) film grown by PECVD system and post-annealing. The formation and quantum confinement effect (QCE) of a-Si QDs embedded in SRO film grown with relatively low annealing temperature (300℃) are demonstrated.

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In this study, type-II GaSb/GaAs quantim dot circular phonotic crystal laser was demonstrated. Lasing action was achieved with wavelength around 961 nm at 150 K temperature. Not only long photon lifetimes were measured by time-result photonluminescence technique but also high Purcell factor were observed when QD emission coupled into high-Q photonic crystal cavity mode.

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An active mode-locked SOA fiber laser with the repetition rate of 10 GHz is demonstrated by EO phase modulation. The laser can be operated under the single wavelength state and the dual wavelength state with the adjustment of pump current and light polarization. Its application for measuring fiber dispersion is also demonstrated.

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To realize the destination of optical integrated circuits, miniaturizing optical device which can generate high intensity coherent sources appeals to many people to research. In this study, we report surface plasmonic lasers comprised of 5nm silica gap layer between ZnO nanowire and silver film. The lasing wavelength is located at the region of interband absorption of silver. In this region, the refractive index of silver varies sharply, as a result, the group index is large. Owning large group index means photons can effectively interact with gain medium and surface plasmon.

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We investigated GaN-based vertical cavity surface emitting lasers (VCSELs) with an optical confinement aperture, and verified the transverse optical confinement characteristics using shallow etched mesa in the GaN-based VCSEL.

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Two stacks of multiple quantum wells have been used for integrating electroabsorption modulator (EAM) and DFB laser. Traveling wave electrode is designed for high speed operation, leading to SMSR of above 35dB, -3dB bandwidth of above 40GHz, and 40Gb/s performance.

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We reported the use of PEC-Ga2O3 for gate-oxide and PEALD-Al2O3 for passivation on AlGaN/GaN MOS-HEMT to achieve on/off ratio of 10^10. Our method allows Vth to increase from -4V to -1.77V by increasing oxide thickness while keeping gm and Id,sat unchanged. Device-parameter-extraction suggests this device could become enhancement-mode as PEC-oxide exceeds 18.5nm.

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Terahertz time-domain spectroscopy (THz-TDS) system and the related technology and its applications in capital normal university (CNU) are presented. Most often used THz-TDS system as a spectroscopic measurement setup in our lab is introduced in detail, including THz radiation source, THz detection method and its measurement and control system. THz spectra of some materials measured in CNU is summarized and discussed. These materials include but not limited to two kinds of typical matter - the illegal drugs and the explosives, the biological macro-molecules, the cosmetics and the fine chemical materials, the edible pigments and the food additives, the homocysteic acid and related compounds, the heavy ions in soil, the Chinese medicines, the tobacco and crops, the oil and chemical products, the carbon nanotubes, the superconductors, and various semiconductors and their heterojunctions, are presented. THz emission from InAs and InN semiconductor surface are compared. THz spectral investigation of metallic mesh structures is summarized. Finally, an outlook of THz spectroscopic application on metamaterials characteristic is presented briefly.

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We theoretically demonstrate a clear and straightforward approach, which just relies on a simple DC spatially gradient electric potential, for robustly generating bright chirp-free attosecond pulses of electromagnetic radiation throughout the soft X-ray region of the spectrum with pulse durations in the single-digit attosecond range.

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An ideal freestanding graphene in air is centrosymmetric in three dimensions, and its optical second harmonic generation is inhibited. However, we found strong second harmonic generation from suspended single-layer graphene, and attributed this observation to curved sheet in the long range.

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A numerical study of maximum extractable energy for Ytterbium-doped high-power pulsed fiber laser amplifiers is presented. The influence of stimulated Raman scattering on amplified processes is considered. The simulation results show the criterions of seed energy and width to suppress Stokes waves. Optimized experimental parameters are suggested in this contribution.

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A 800 nm Ti: sapphire laser is transferred to a transform limit 400 nm by SHG through the BBO crystal. We passed the 400 nm light through a set of fused silica plates to generate a broadband continuum ranging from 320 nm to 480 nm by four-wave mixing and filamentation.

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The diffraction efficiency spectrum of PQ-PMMA volume Bragg grating (VBG) depends on the absorption coefficient and refractive index modulation of PQ-PMMA. The peak diffraction efficiency can shift more than 0.2 nm from the intended written wavelength.

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A tunable dual single longitudinal modes laser is built using two homemade PQ-PMMA volume Bragg gratings (VBG) as the wavelength selecting and spectral narrowing elements. The laser can achieve the wavelength tunning range more than 10 nm without damage the PQ-PMMA VBGs.

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We present the modeling of dipolar exciton ground state in AlGaAs asymmetric coupled quantum wells in an external electric field induced two-dimensional electrostatic trap. It is shown that a stable spontaneous emission can be obtained where its radiative lifetime approaches 50 ps.

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A continuous-wave mode-locking laser system via positive cascaded second-order Kerr lens (CSKL) at 1063 nm was demonstrated. An average power of 3.49 W is obtained under 19.5 W diode power at 808 nm. The pulse repetition rate, and the pulse duration are 175.44 MHz, and 18 ps, respectively.

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In this paper, a simulation program using Non- Equilibrium Greens function formalism with electron-phonon (acoustic and polar optical phonon) is developed for studying carrier transport with energy relaxation. The result shows thatthe carrier energy of the current density would be broadened after applying the scattering. The result suggests that a proper scattering consideration should be considered in most quantum transport model.

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We report the study of the finite-beam　Bragg diffraction behavior of an electro-optic volume grating made of a PPLN crystal. The experimental observations show that the diffraction mode pattern and diffraction efficiency of the PPLN EO Bragg device are closely related to the interaction beam size and applied voltage.

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When the interaction of orthogonally polarised modes with the active medium occurs, the low-frequency relaxation oscillation for antiphase mode will be generated. This work demonstrates the dynamics corresponding to pump modulation frequency approaching to this low frequency. The relationship of average frequency of chaotic signal between in-phase and anti-phase oscillation were studied.

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We used the nonlinear Schrödinger equation to model the process of continuum generation using multiple thin plates. The result is compared with experiments done with an 800 nm femtosecond laser pulse.

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Graphene thin-films were prepared by CVD method with different layers and measured by Z-scan technique. Results showed that nonlinear absorption was due to saturation of single photon absorption. Under the intensity of 21.3 GW/cm2, 1- and 8-layer graphene showed the nonlinear absorption coefficient α(I) of 1.342 and 0.043 (10^8 m-1).

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In this study, GaN-based photonic quasi-crystal surface emitting lasers (PQCSELs) were fabricated and analyzed. The device for Γ5 mode exhibited the lowest threshold pumping energy density of 4.6 mJ/cm2. The tendency of calculated gains was consistent with the experiment results. We concluded that the PQCSEL had the opportunity to acquire lower threshold energy density than conventional PCSEL if it operated at special band-edge mode.

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Self-phase modulation (SPM) and group delay dispersion (GDD) managed erbium-doped fiber laser (EDFL) mode-locked with few-layer graphene nano-sheet is demonstrated to optimize the soliton compression at a negative GDD region.

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The characteristic difference between forward- and backward-pumped ytterbium-doped fiber laser is investigated. In the forward pumping scheme, the over-pumping power can be reused in the next cycle to enhance the gain in the fiber cavity. Therefore, higher output power and slope can be obtained.

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In this paper, we demonstrated the chirped pulse amplification (CPA) of a high-power ytterbium-doped fiber amplifier at wavelength of 1064 nm without a stretcher. The all-normal dispersion (ANDi) passively mode-locked fiber laser is used to generate highly chirped seed pulse. Further, the compressed-pulse was frequency doubled by a type-I critically phase-matched (CPM) Lithium Triborate (LBO) crystal. With 370 mW of fundamental light, we can generate 88 mW of green output (λ= 532 nm) with conversion efficiency of 23%.

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The silicon carbide saturable absorbers with varying C/Si composition ratios are employed to passively mode-lock the fiber laser for compressing the pulsewidth from 400 fs to 360 fs with a time-bandwidth product of 0.317 when varying the SixC1-x from the stoichiometric to C-rich condition.

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We used Z-scan without aperture technique to measurement the nonlinear optical absorption properties of gold-nanoparticle films. We use sample is 3-Mercaptopropionic acid (MPA). Those gold-nanoparticle films was comprised by diameter 12nm with two layers(MPA1) and three layers(MPA2). And those samples’ UV-Visible absorption characteristics show in Figure. Then we studied those samples at off-resonant wavelengths and the result of fitting data are showing in table . Our laser light source is mode-locked femtosecond Ti:sapphier laser(790nm,120fs).

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We reported that spectrally-resolved two-beam coupling [1] using a mode-locked Ti:sapphire laser produces reliable measurements of the nonlinear responses of fused silica. The nonlinear index of refraction of fused silica n_2=3.18×〖10〗^(-20) m2/W. Figures 1, 2 show experiment results on fused-silica at 780 and 800nm, respectively.

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A nonlinear system with chirp depending disperion is modelled and nonlinear wave dynamics therein is investigated. One stable unchirped soliton and one unstable chirped soliton families are supported. Potentially efficient spectral and pulse compression devices are proposed.

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Laser noise properties such as amplitude jitter and timing jitter during spectral compression process are experimentally characterized. Our results show that improvement on amplitude jitter can be achieved for all input pulse chirp values, while improvement on timing jitter is limited to negatively input chirps.

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Green frequency comb generation from 510 to 555nm spectral range was reported on chirp-PPLN with mode spacing 450GHz same as the pump QPM-OPO frequency comb due to the concurrence of multi-wavelength SHG and SFG processes.

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The negative and positive Goos-Hanchen (GH) shifts in the reflected light is investigated for a partial coherent light incident on a cavity containing a four-level Raman gain medium. The effect of spatial coherence and higher-order modes of partial coherent light fields is studied on the negative and positive GH shifts.

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We verify that the observations of exciton-polariton lasing effects in a ZnO microrod investigated by angle-resolved micro-photoluminescence spectroscopy at room temperature. Above threshold, the exciton-polariton condensation can be observed in dispersion spectra at k//=0. The results of Young’s double-slit experiment show the spatial coherence properties of the microcavity polaritons.

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We demonstrated an integrated system that can manipulate and measure full-vectorial frequency combs (the optical field of ultimate complexity in time domain) without any reference.

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