2016
2016
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Record 169 of
Title:Experimental demonstration of 3D Accelerating beam arrays
Author(s):Yu, Xianghua(1); Li, Runze(1); Yan, Shaohui(1); Yao, Baoli(1); Gao, Peng(1); Han, Guoxia(1); Lei, Ming(1)Source: Applied Optics Volume: 55 Issue: 11 DOI: 10.1364/AO.55.003090 Published: April 10, 2016Abstract:Accelerating beams have attracted much attention in the frontiers of optical physics and technology owing to their unique propagation dynamics of nondiffracting, self-healing, and freely accelerating along curved trajectories. Such behaviors essentially arise from the particular phase factor occurring in their spatial frequency spectrum, e.g., the cubic phase associated to the spectrum of Airy beam. In this paper, we theoretically and experimentally demonstrate a sort of accelerating beam arrays, which are composed of spatially separated accelerating beams. By superimposing kinoforms of multifocal patterns into the spatial frequency spectrum of accelerating beams, different types of beam arrays, e.g., Airy beam arrays and two-main-lobe accelerating beam arrays, are generated and measured by scanning a reflection mirror near the focal region along the optical axis. The 3D intensity patterns reconstructed from the experimental data present good agreement with the theoretical counterparts. The combination of accelerating beams with optical beam arrays proposed here may find potential applications in various fields such as optical microscopes, optical micromachining, optical trapping, and so on. ? 2016 Optical Society of America.Accession Number: 20161702281929 -
Record 170 of
Title:MoS2-Mode-Locked Fiber Laser Delivering Ultrashort Pulses with Three Types of Sidebands
Author(s):Lu, Feifei(1); Liu, Xueming(1); Yang, Huiran(1)Source: Optics InfoBase Conference Papers Volume: Issue: DOI: Published: August 29, 2016Abstract:We demonstrate an erbium-doped fiber laser passively mode-locked by a monolayer MoS2 which is covered onto a fiber taper. Three types of sidebands, e.g. peak, peakdip and dipspectral sidebands, are observed in the experiment. ? 2016 OSA.Accession Number: 20171403544755 -
Record 171 of
Title:MoS2-mode-locked fiber laser delivering ultrashort pulses with three types of sidebands
Author(s):Lu, Feifei(1); Liu, Xueming(1); Yang, Huiran(1)Source: Optics InfoBase Conference Papers Volume: Issue: DOI: 10.1364/BGPP.2016.JM6A.1 Published: August 29, 2016Abstract:We demonstrate an erbium-doped fiber laser passively mode-locked by a monolayer MoS2 which is covered onto a fiber taper. Three types of sidebands, e.g. peak, peak-dip and dip spectral sidebands, are observed in the experiment. ? OSA 2016.Accession Number: 20171403516004 -
Record 172 of
Title:Fast DMD based super-resolution structured illumination microscopy
Author(s):Lei, Ming(1); Zhou, Xing(1); Dan, Dan(1); Qian, Jia(1); Yao, Baoli(1)Source: Optics InfoBase Conference Papers Volume: Issue: DOI: 10.1364/FIO.2016.FF3A.5 Published: 2016Abstract:Structured illumination microscopy (SIM) is an attractive choice for fast superresolution imaging. The generation of structured illumination patterns made by interference of laser beams is broadly employed to obtain high modulation depth of patterns, while the polarizations of the laser beams must be elaborately controlled to guarantee the high contrast of interference intensity, which brings a more complex configuration for the polarization control. The emerging pattern projection strategy is much more compact, but the modulation depth of patterns is deteriorated by the optical transfer function (OTF) of the optical system, especially in high spatial frequency near diffraction limit. Therefore, the traditional super-resolution reconstruction algorithm for interference-based SIM will suffer from much artifact in the case of projection-based SIM that possesses a low modulation depth. Here, we propose an alternative reconstruction algorithm based on image recombination transform (IRT), which provides an alternative solution to address this problem even in a weak modulation depth. We demonstrated the effectiveness of this algorithm in the multicolor super-resolution imaging of BPAE cells in our developed projection-based SIM system, which applies a computer controlled digital micro-mirror device (DMD) for fast fringe generation and multicolor LEDs for illumination. The merit of the system incorporated with the proposed algorithm allows for a low excitation intensity fluorescence imaging even less than 1W/cm2, which is beneficial for the long-term, in vivo super-resolved imaging of live cells and tissues. ? OSA 2016.Accession Number: 20171503548085 -
Record 173 of
Title:Optically induced rotation of Rayleigh particles by vortex beams with different states of polarization
Author(s):Li, Manman(1); Yan, Shaohui(1); Yao, Baoli(1); Liang, Yansheng(1); Lei, Ming(1); Yang, Yanlong(1)Source: Physics Letters, Section A: General, Atomic and Solid State Physics Volume: 380 Issue: 1-2 DOI: 10.1016/j.physleta.2015.08.026 Published: July 2, 2015Abstract:Optical vortex beams carry optical orbital angular momentum (OAM) and can induce an orbital motion of trapped particles in optical trapping. We show that the state of polarization (SOP) of vortex beams will affect the details of this optically induced orbital motion to some extent. Numerical results demonstrate that focusing the vortex beams with circular, radial or azimuthal polarizations can induce a uniform orbital motion on a trapped Rayleigh particle, while in the focal field of the vortex beam with linear polarization the particle experiences a non-uniform orbital motion. Among the formers, the vortex beam with circular polarization induces a maximum optical torque on the particle. Furthermore, by varying the topological charge of the vortex beams, the vortex beam with circular polarization gives rise to an optimum torque superior to those given by the other three vortex beams. These facts suggest that the circularly polarized vortex beam is more suitable for rotating particles. ? 2015 Elsevier B.V.Accession Number: 20202208737929 -
Record 174 of
Title:Passively mode-locked erbium-doped fiber laser via a D-shape-fiber-based MoS2 saturable absorber with a very low nonsaturable loss
Author(s):Duan, Li-Na(1); Su, Yu-Long(1); Wang, Yong-Gang(1); Li, Lu(1); Wang, Xi(1); Wang, Yi-Shan(1)Source: Chinese Physics B Volume: 25 Issue: 2 DOI: 10.1088/1674-1056/25/2/024206 Published: January 10, 2016Abstract:We report on the generation of conventional and dissipative solitons in erbium-doped fiber lasers by the evanescent field interaction between the propagating light and a multilayer molybdenum disulfide (MoS2) thin film. The MoS2 film is fabricated by depositing the MoS2 water-ethanol mixture on a D-shape-fiber (DF) repetitively. The measured nonsaturable loss, saturable optical intensity, and the modulation depth of this device are 13.3%, 110 MW/cm2, and 3.4% respectively. Owing to the very low nonsaturable loss, the laser threshold of conventional soliton is as low as 4.8 mW. The further increase of net cavity dispersion to normal regime, stable dissipation soliton pulse trains with a spectral bandwidth of 11.7 nm and pulse duration of 116 ps are successfully generated. Our experiment demonstrates that the MoS2-DF device can indeed be used as a high performance saturable absorber for further applications in ultrafast photonics. ? 2016 Chinese Physical Society and IOP Publishing Ltd.Accession Number: 20160701930542 -
Record 175 of
Title:The influence of thermal and free carrier dispersion effects on all-optical wavelength conversion in a silicon racetrack-shaped microring resonator
Author(s):Wang, Zhaolu(1); Liu, Hongjun(1); Sun, Qibing(1); Huang, Nan(1); Li, Shaopeng(1); Han, Jing(1)Source: Laser Physics Volume: 26 Issue: 7 DOI: 10.1088/1054-660X/26/7/075403 Published: July 2016Abstract:We experimentally demonstrate ultra-low pump power wavelength conversion based on four-wave mixing in a silicon racetrack-shaped microring resonator. When the pump and signal are located at the resonance wavelengths, wavelength conversion with a pump power of only 1 mW can be realized in this microring resonator because of the resonant enhancement of the device. However, saturation of the conversion efficiency occurs because of the shift of the resonance peak, which is caused by the change of the effective refractive index induced by a combination of thermal and free carrier dispersion effects, and it is demonstrated that the thermal effect is the leading-order factor for the change of the refractive index. The maximum conversion efficiency of -21 dB is obtained when the pump power is less than 12 mW. This ultra-low-power on-chip wavelength convertor based on a silicon microring resonator can find important potential applications in highly integrated optical circuits for all-optical signal processing. ? 2016 Astro Ltd.Accession Number: 20162902595935 -
Record 176 of
Title:Numerical analysis of pulse signal restoration by stochastic resonance in a buckled microcavity
Author(s):Sun, Heng(1); Liu, Hongjun(1); Sun, Qibing(1); Huang, Nan(1); Wang, Zhaolu(1); Han, Jing(1)Source: Applied Optics Volume: 55 Issue: 12 DOI: 10.1364/AO.55.003351 Published: April 20, 2016Abstract:A novel scheme is proposed to restore weak pulse signals immersed in noise by stochastic resonance based on photothermal-effect-induced optical bistability in a buckled dome microcavity. The bistable properties of the dome microcavity are analyzed with different initial detuning wavelengths and effective cavity lengths, and bistable transmission can be obtained for input powers in submilliwatt range. A theoretical model is derived to interpret the nonlinear process of pulse signal recovery through double-well potential theory. The cross-correlation coefficient between output signals and pure input pulses is calculated to quantitatively analyze the influence of noise intensity on stochastic resonance. A cross-correlation gain of 7 is obtained, and the noise-hidden signal can be recovered effectively though the buckled dome microcavity with negligible distortion. The simulation results show the potential of using this structure to restore low-level or noise-hidden pulse signals in all-optical integrated systems. ? 2016 Optical Society of America.Accession Number: 20162302476170 -
Record 177 of
Title:Ytterbium-doped double-cladding fiber with 3.5 kW output power, fabricated by chelate gas phase deposition technique
Author(s):Hou, Chaoqi(1); Zhu, Yonggang(1); Zheng, Jinkun(1); Li, Gang(1); Li, Chao(1); Gao, Song(1); Gao, Qi(1); Zhang, Lihua(1); Chang, Chang(1); Zhao, Wei(1); Li, Weinan(1); Zhao, Baoyin(1)Source: Optical Materials Express Volume: 6 Issue: 4 DOI: 10.1364/OME.6.000979 Published: April 1, 2016Abstract:A ytterbium-doped double-cladding fiber was successfully fabricated by a chelate gas phase deposited technique. The measurement results of dopant concentration distribution and refractive index of preform indicate that radial and longitudinal homogeneity could be controlled perfectly with this technique. The absorption coefficients of fiber are 0.39 dB/m at 915nm and 1.02 dB/m at 976nm respectively. Using this fiber as the laser amplifier stage, 3592W output power at 1080nm with 72.5% slope efficiency was obtained with end-pump technique, which is close to the test results of Nufern commercial fiber. The results demonstrate that the chelate gas phase deposition technique is a relatively promising technique for high quality gain fiber fabrication. ? 2016 Optical Society of America.Accession Number: 20162602537553 -
Record 178 of
Title:50 μj Femtosecond Laser System Based on Strictly All-Fiber CPA Structure
Author(s):Li, Feng(1,2,3); Yang, Zhi(1); Zhao, Wei(1,3); Li, Qianglong(1); Zhang, Xin(1,2); Yang, Xiaojun(1); Zhang, Wei(1); Wang, Yishan(1,3)Source: IEEE Photonics Journal Volume: 8 Issue: 5 DOI: 10.1109/JPHOT.2016.2614600 Published: October 2016Abstract:We demonstrate a strictly all-polarization maintaining, all-fiber chirped pulse amplification of ultrashort pulses. Pulses with the duration of 933 fs and energy as high as 50 μJ are achieved at 200 kHz repetition rate in a compact size. The variations of the spectra and pulse widths as functions of the amplified output power have also been presented. To our best knowledge, this is the highest energy extracted from the strictly all-fiber chirped pulse amplification system. The environmentally stable femtosecond laser source will find various applications in practice. ? 2016 IEEE.Accession Number: 20164703027225 -
Record 179 of
Title:Holographic optical trapping and manipulation based on phase-only liquid-crystal spatial light modulator
Author(s):Liang, Yansheng(1); Yao, Baoli(1); Ma, Baiheng(1); Lei, Ming(1); Yan, Shaohui(1); Yu, Xianghua(1)Source: Guangxue Xuebao/Acta Optica Sinica Volume: 36 Issue: 3 DOI: 10.3788/AOS201636.0309001 Published: March 10, 2016Abstract:An improved and rapid three dimensional Gerchberg-Saxton (GS) algorithm based on the classic GS algorithm for computer generated holograms is proposed and applied to holographic optical tweezers. Theoretical simulations and experimental results have demonstrated the rapidity and efficiency of the proposed algorithm. A robust holographic optical tweezers setup based on phase-only liquid-crystal spatial light modulator(SLM) is built, and stable trapping and dynamic manipulation of yeast cells and silica beads with large array traps in three dimensions are demonstrated. Two special traps, i.e., line trap with intensity gradient distribution and optical vortex trap, are generated to transport and rotate micro-particles respectively. The system is verified to be robust on particles manipulations, which provides a new and powerful tool for researches on biology, colloid physics and so on. ? 2016, Chinese Laser Press. All right reserved.Accession Number: 20161302145087 -
Record 180 of
Title:Influence of absorption on stability of terahertz difference frequency generation
Author(s):Huang, Nan(1); Liu, Hongjun(1); Sun, Qibing(1); Wang, Zhaolu(1); Li, Shaopeng(1); Han, Jing(1)Source: Applied Optics Volume: 55 Issue: 3 DOI: 10.1364/AO.55.000444 Published: January 20, 2016Abstract:This work presents numerical studies of the stability feature of terahertz difference frequency generation (THz-DFG) with a ZnGeP2 crystal using two pump wavelengths. We found that the maximum output of a THz wave is located in the unstable output region because of the competitive equilibrium between the absorption and the gain. Furthermore, the output stability is dependent on the pump stability. Different from the results at the pump wavelength of 9.588 μm, there is neither an appropriate stable output region nor gain saturation region at the pump wavelength of 1.064 μm for a larger absorption coefficient. This work demonstrates that the stable output region of the THz wave is difficult to obtain when the pump absorption is excessively large in DFG. ? 2016 Optical Society of America.Accession Number: 20161402181281