Adzir Mahdi Mohd   Kuen Yao Lau   Pin Jern Ker   Abas Ahmad Fauzi   Alresheedi Mohammed Thamer  

      摘要 + ：(浏览：18次) | 此论文可免费阅读 (可能需要登录)

Saturable absorber is commonly employed to generate ultrashort laser with mode-locking scheme. In an erbium-doped fiber laser system, the laser regimes either 1530 nm or 1550 nm wavelength are procured based on the absorption profile of the erbium-doped fiber. The absorption of erbium-doped fiber is designed to emit at both wavelengths by control the net gain of the laser cavity. Subsequently, simultaneous erbium-doped fiber laser emission is attained at 1533.5 nm and 1555.1 nm with the pulse duration of 910 fs and 850 fs, respectively. Therefore, this work maximizes the output portfolios of mode-locking fiber laser for dual-wavelength ultrashort pulses emission.

       PDF全文 (下载：9)        Chinese Optics Letters ，2019年第17卷第5期 pp.05      

cao zhen   He Hongbo   Hu Guohang   Zhao Yuanan   Yang Liujiang   Shao Jianda  

      摘要 + ：(浏览：17次) | 此论文可免费阅读 (可能需要登录)

A time-resolved high-power laser photometer, which measures the real-time variations of transmission, internal reflection, and scattering simultaneously with picosecond time resolution, was developed to investigate the material response sequence during high-power nanosecond laser irradiation in thick fused silica. It was found that the transient transmission decreased sharply accompanied with an increase in internal reflection at the rising edge of the laser pulse. The transient transmission recovered while laser damage did not occur, but it did not recover if the scattering increased, indicating the occurrence of laser damage. The reason of sharp-decrease of transmission and the relationship between the transmission drop and laser damage were discussed.

       PDF全文 (下载：4)        Chinese Optics Letters ，2019年第17卷第5期 pp.05      

zhang jingang   Nie Yunfeng   Fu Q.   Peng Yifan   Xiang Libin  

      摘要 + ：(浏览：19次) | 此论文可免费阅读 (可能需要登录)

Conventional optical system design employs combinations of different lenses to combat aberrations, which usually leads to considerable volume and weight. In this paper, a tailored design scheme that exploits state-of-the-art digital aberration correction algorithms in addition to traditional optics design is investigated. In particular, the proposed method is applied to the design of refractive telescopes by shifting the burden of correcting chromatic aberrations to software. By enforcing cross-channel information transfer in a post-processing step, the uncorrected chromatic aberrations are well mitigated. Accordingly, a telescope of f-8, 1,400mm focal length, and 0.14° field of view is designed with only two lens elements. The image quality of the designed telescope is evaluated by comparing it to the equivalent designs with multiple lenses in a traditional optical design manner, which validates the effectiveness of our design scheme.

       PDF全文 (下载：3)        Chinese Optics Letters ，2019年第17卷第5期 pp.05      

Li Shasha   Shen Baifei   Wang Wenpeng   Bu Zhigang   Zhang Hao   Zhang Hui   Zhai Shuhua  

      摘要 + ：(浏览：20次) | 此论文可免费阅读 (可能需要登录)

Vortex harmonics with fractional average orbital angular momentum are generated when a relativistic fractional vortex beam incidents on and reflects from an overdense plane plasma target. A two-step model is presented to explain the far-field patterns of the harmonics. In the first step, a fundamental spot-shaped hole is produced during the hole-boring (HB) stage, and harmonics are generated simultaneously. In the second step, different order harmonics are diffracted by the hole and propagate to the far-field. This process can be accurately described by Fraunhofer diffraction theory. This work facilitates a basic recognition of fractional vortex beams.

       PDF全文 (下载：4)        Chinese Optics Letters ，2019年第17卷第5期 pp.05      

Guo Xi   Xing Zhikun   Qin Huabao   Sun Qizhen   Liu Deming   Zhang Lin   Yan Zhijun  

      摘要 + ：(浏览：25次) | 此论文可免费阅读 (可能需要登录)

We have investigated the whole polarization-extinction-ratio (PER) spectrum and annealing properties of 45°-tilted fiber gratings (45°-TFGs). Experimental results show the PER spectrum of 45°-TFGs is Gaussian-like profile and covers 540nm bandwidth form 1260 to 1800nm, in which the bandwidth with PER greater than 10dB is over 250nm. The output polarization distribution of 45°-TFGs was analyzed by employing a bulk linear polarizer, and the results show a perfect figure “8”, which indicates that the 45°-TFG is a type of linear polarizer. Moreover, the annealing property of 45°-TFGs was measured up to 700 ℃, in which the PER of grating started to decrease at 300℃ and reached to the minimum at 700℃. Based on these results, the 45°-TFGs can be used as ultra-wide bandwidth in-fiber polarizing devices.

       PDF全文 (下载：2)        Chinese Optics Letters ，2019年第17卷第5期 pp.05      

Shi Nuannuan   Li Wei   Zhu Ninghua   Li Ming  

      摘要 + ：(浏览：23次) | 此论文可免费阅读 (可能需要登录)

To overcome the beam squint in wide instantaneous frequency, we review a number of system level optical controlled phase array antenna (OCPAA) for beam forming. The optical delay network based on fiber device in terms of topological structure of N-bit optical switch, fiber grating, high-dispersion fiber, vector-sum technology is discussed, respectively. At last, integrated circuit is simply summarized.

       PDF全文 (下载：5)        Chinese Optics Letters ，2019年第17卷第5期 pp.05      

SHAO DIXIANG   Chen Yao   Zhou T.   Zhang R.   FU ZHANGLONG   Zhuang Songlin   Cao Juncheng  

      摘要 + ：(浏览：24次) | 此论文可免费阅读 (可能需要登录)

Optical frequency combs, which are generated by the cascade of a phase modulator and a Mach-Zehnder intensity modulator, are used as a polychromatic signal source in the terahertz imaging system to improve imaging quality. Interference effect caused by the monochromatic wave has been greatly suppressed. The required optical power in the presented system is as low as ~30% of that in the system using the Er-doped fiber amplifier as source, which can reduce cost and protect photodiodes from damage. This work provides an effective, low power consumption, low cost, and easy way to realize terahertz imaging with high quality, and can be used in the future security inspection.

       PDF全文 (下载：2)        Chinese Optics Letters ，2019年第17卷第4期 pp.04      

Yan Dongyu   Liu Bowen   Chu Yuxi   Song Huanyu   Chai Lu   Hu Minglie   Wang Qingyue  

      摘要 + ：(浏览：28次) | 此论文可免费阅读 (可能需要登录)

We report a hybrid femtosecond laser system based on a femtosecond Yb-doped fiber laser and an Yb:KGW regenerative amplifier. To match the central wavelength of the seed source, an Yb:KGW crystal is used in the regenerative amplifier for Np-polarization. We study and optimize the dynamics of nonlinear amplification to alleviate the gain narrowing effect. With optimization, the system can output 270-fs pulses with 21-μJ pulse energy at a 60-kHz repetition rate.

       PDF全文 (下载：0)        Chinese Optics Letters ，2019年第17卷第4期 pp.04      

Zhan Yueying   He Jianhua   Wang Fei   Wang Liqian  

      摘要 + ：(浏览：33次) | 此论文可免费阅读 (可能需要登录)

In our paper, we selected several commercial optical transceivers, which consist of single-channel transceiver modules, parallel transmitting and receiving modules, and EPON OLT and ONU modules, to do the total ionizing dose (TID) testing via gamma-ray radiation method. The changing of current and receiver sensitivity of optical transceivers are discussed and analyzed. Based on the TID testing exposed to a total ionizing dose of 50 krad (Si) at a dose rate of about 0.1 rad (Si)/s, the performance of single-channel transceivers and parallel receiving modules have not changed after 50 krad (Si) exposed, the parallel transmitting and EPON ONU modules have not worked after 40 krad (Si) and 47 krad (Si) exposed, the EPON OLT module has bit error in the process of irradiation and it can work well after annealing, and the reason for the error of OLT is analyzed. Finally, based on the theoretical analyzed and testing results, this paper provides several design suggestions to improve the reliability for optical transceivers, which can be referenced by satellite system designation for various space missions.

       PDF全文 (下载：2)        Chinese Optics Letters ，2019年第17卷第5期 pp.05      

zhang yanjun   Li Yunchao   Hu Xuwen   Zhang Lu   Liu Zhaojun   Zhang Kaifang   Mou Shihao   Zhang Shougang   Yan Shu-Bin  

      摘要 + ：(浏览：28次) | 此论文可免费阅读 (可能需要登录)

As the key part of chip-scale atomic clocks (CSACs), the vapor cell directly determines the volume stability and power consumption of the CSAC. The reduction of the power consumption and CSAC volumes demands the manufacture of corresponding vapor cells. However, their micro-fabrication is challenging. This overview presents the research development of vapor cells of the past few years and analyzes the shortages of the current preparation technology. By comparing several different vapor cell preparation methods, we successfully realized the micro-fabrication of vapor cells using anodic bonding and deep silicon etching. The microelectromechanical system (MEMS) fabrication process is presented in detail. It is simple and avoids weak bonding strengths caused by alkali metal volatilization during anodic bonding under high temperatures. Finally, the vapor cell D2 line was characterized via optical absorption resonance. According to the results, the proposed method is suitable for CSAC.

       PDF全文 (下载：3)        Chinese Optics Letters ，2019年第17卷第4期 pp.04      

Sun Han   wang Lan   Zhang Yaxin   Liang Shixiong   Han Jiaguang   Lan Feng   Zhou Xinlan   Yang Ziqiang  

      摘要 + ：(浏览：27次) | 此论文可免费阅读 (可能需要登录)

This paper presents a double layer structure combined with cracked cross meta-surface and grating surface to realize arbitrary incident linear THz wave polarization conversion. The arbitrary incident linear polarization THz wave will be induced the same resonant modes in the unit-cell, which results in polarization conversion insensitive to the linear polarized angel. Moreover, the zigzag-shaped resonant surface current leads to a strong magnetic resonance between the meta-surface and gratings, which enhanced the conversion efficiency. The experimental results show more than 70% conversion rate can be achieved under arbitrary linear polarized within a wide frequency band. Moreover, around 0.89THz nearly perfect polarization conversion is realized.

       PDF全文 (下载：1)        Chinese Optics Letters ，2019年第17卷第4期 pp.04      

Li Hui   Zhao Qingchao   Jiang Shaodong   Ni Jiasheng   Wang Chang  

      摘要 + ：(浏览：29次) | 此论文可免费阅读 (可能需要登录)

A fiber Bragg grating (FBG) and Fabry-Perot (FP) cavity cascaded fiber sensing system was manufactured for temperature and pressure sensing. Temperature high up to 175 ℃ sensing was performed by FBG for the linear variation of FBG wavelength with temperature. After temperature was sensed, the demodulation system can find the original FP cavity length and its pressure-cavity length correlation coefficient, thus the ambient pressure would be calculated. The sensing pressure can be as high as 100 MPa with a repeatability of 1/10000 and high stability. This kind of fiber sensor has been used in Shengli Oil Field.

       PDF全文 (下载：1)        Chinese Optics Letters ，2019年第17卷第4期 pp.04      

Gong Dejing   Yuan Yinquan   Liang Lei   Yang Minghong  

      摘要 + ：(浏览：28次) | 此论文可免费阅读 (可能需要登录)

Using theoretical simulations for optical fiber surface plasmon resonance (SPR) sensor and prism based SPR sensor coated with negative permittivity material (NPM), we investigated the effect of the permittivity of NPM on the transmitted spectrum of optical fiber SPR sensor and the reflected spectrum of prism based SPR sensor, and then obtained optimum permittivity of the NPM which can excite the sharpest SPR spectrum in white light region (400-900 nm).

       PDF全文 (下载：3)        Chinese Optics Letters ，2019年第17卷第4期 pp.04      

Shahzadi Mahnoor   Zhang W. L.   Talha Muhammad  

      摘要 + ：(浏览：49次) | 此论文可免费阅读 (可能需要登录)

Exciton-polaritons offer an exceptional platform for future photoelectronic and quantum information applications. The influence of optical Stark effect on exciton-polariton in microcavity embodied with a monolayer WS2 is studied. A polarization dependent model is proposed to study the change of strongly coupled excitons and photons in WS2 microcavity. It is revealed through both steady and dynamical states analysis that an outside optical Stark pulse can effectively vary the polariton characteristics such as dispersion, exciton and photon fractions through blue shifting of excitonic resonance. Thus, the analysis and control of excitons-polaritons in a WS2 microcavity via spin-selective trigger could be achievable.

       PDF全文 (下载：4)        Chinese Optics Letters ，2019年第17卷第2期 pp.02      

Ma Yuxuan   Meng Fei   Wang Yan   Wang Aimin   Zhang Zhigang  

      摘要 + ：(浏览：44次) | 此论文可免费阅读 (可能需要登录)

We demonstrate a 0.95 GHz repetition rate fully stabilized Yb:fiber frequency comb without optical amplification. Benefitted from the high mode power and high coherence, this comb achieved 35 dB to 42 dB signal to noise ratio on the direct heterodyne beat signals with at least 6 continuous wave lasers (at 580nm, 679nm, 698nm, 707nm, 813nm and 922 nm) while keeping >40 dB carrier envelop frequency signal. It can be used for the direct measurement of optical frequencies in visible and near-infrared wavelengths, and has a great potential on simultaneous comparison of multiple optical frequencies.

       PDF全文 (下载：1)        Chinese Optics Letters ，2019年第17卷第4期 pp.04      

Qian Qizhang   Wang Nan   Zhao Shengzhi   Li Guiqiu   Li Tao   Li Dechun   Yang Kejian   Zang Jie   Ma Houyi  

      摘要 + ：(浏览：42次) | 此论文可免费阅读 (可能需要登录)

Gold nanorods (GNRs) with two different aspect ratios were successfully utilized as saturable absorbers (SAs) in passively Q-switched Nd:LLF laser emitting at 1.34 μm. Based on the GNRs with an aspect ratio of 5, a maximum output power of 1.432 W was achieved, and the narrowest pulse width was 328 ns with a repetition rate of 200 kHz. But in the case of the GNRs with the aspect ratio of 8, a maximum output power of 1.247 W was achieved, and the narrowest pulse width was 271 ns with a repetition rate of 218 kHz. Our experimental results reveal that the aspect ratios of GNRs have different saturable absorption effects at a specific wavelength. In other words, for passively Q-switched lasers at a given wavelength, we are able to select the most suitable GNRs as an SA by changing their aspect ratio.

       PDF全文 (下载：2)        Chinese Optics Letters ，2019年第17卷第4期 pp.04      

Li Zhuang   lv xiaoyi  

      摘要 + ：(浏览：45次) | 此论文可免费阅读 (可能需要登录)

Echinococcosis—a parasitic disease caused by Echinococcus granulosus or Echinococcus multilocularis larvae—occurs in many regions in the world. This disease can pose a serious threat to public health and thus requires a convenient and cost-effective method for early detection. So we developed a novel method based on visual saliency and scale-invariant features, that detects the tapeworm parasites .This method improves upon existing bottom-up computational saliency models by introducing a visual attention mechanism. The results indicated that the proposed method offers a higher level of both accuracy and computational efficiency when detecting Echinococcus granulosus protoscoleces, which in turn could improve early detection of echinococcosis.

       PDF全文 (下载：2)        Chinese Optics Letters ，2019年第17卷第4期 pp.04      

Xiong Baoxing   Gao Fan   Zhang Xiang   Yuan Xiao  

      摘要 + ：(浏览：53次) | 此论文可免费阅读 (可能需要登录)

The two-dimensional angular filter based on volume Bragg gratings in photothermorefractive glass for ns laser pulse is demonstrated. The experimental results show that the near-field beam quality of laser pulse was effectively improved. The near-field modulation and contrast ratio were improved 1.75 and 4.48 times, respectively. The PSD curves showed that the spatial frequencies more than 0.9mm-1 in x direction and 1.2mm-1 in y direction were effectively suppressed.

       PDF全文 (下载：1)        Chinese Optics Letters ，2019年第17卷第4期 pp.04      

YAN Xu   郭 立新   Chen Minjian   Chai Shuirong  

      摘要 + ：(浏览：43次) | 此论文可免费阅读 (可能需要登录)

Vortex splitting is one of the main causes of instability in orbital angular momentum (OAM) modes transmission. Recent advances in OAM modes free-space propagation have demonstrated that abruptly autofocusing Airy vortex beams (AAVBs) can potentially mitigate the vortex splitting effect. However, different modes of vortex embedding will affect the intensity gradients of the background beams, leading to changes in the propagation characteristics of vortex beams. This study presents the unification of two common methods of coupling autofocusing Airy beams with vortices by introducing a parameter (m) which also controls the intensity gradients and focusing properties of the AAVBs. We demonstrate that vortex splitting can be effectively reduced by selecting an appropriate value of the parameter (m) according to different turbulence conditions. In this manner, the performance of OAM-based free-space optical (FSO) systems can be improved.

       PDF全文 (下载：4)        Chinese Optics Letters ，2019年第17卷第4期 pp.04      

Cao Yun   Xiong Jichuan   Liu Xuefeng   Xia Zhiying   Wang Weize   Yadav N.P.   Liu Weiping  

      摘要 + ：(浏览：43次) | 此论文可免费阅读 (可能需要登录)

This paper tackles the issue of non-contact detection of ultrasonic fields by utilizing a novel optical method based on the parametric indirect microscopic imaging (PIMI) technique. A general theoretical model describing the three-dimensional anisotropic photoelastic effect in solid was developed. The mechanism of polarization status variations of light passing through the stress and strain fields was analyzed. Non-contact measurements of ultrasonic field propagating in an isotropic quartz glass have been fulfilled using the PIMI technique under different ultrasonic excitation conditions. PIMI parameters such as sinδ, Φ and the Stokes parameters have been found sensitive to ultrasonic fields.

       PDF全文 (下载：1)        Chinese Optics Letters ，2019年第17卷第4期 pp.04      

Liu kai   Wei Qi   Huang Yongqing   Duan Xiaofeng   Wang Qi   Ren Xiaomin   Cai Shiwei  

      摘要 + ：(浏览：45次) | 此论文可免费阅读 (可能需要登录)

An integrated optoelectronic chip pair which can transmit and receive optical signals simultaneously are proposed in this paper. The design and optimization of its key structure, the VCSEL's DBR, is presented. Analysis is also done for its influence on the integrated chip's performance. Moreover, the chip pair's performance under dynamic conditions are analyzed. Their 3 dB modulation bandwidths are higher than 10 GHz and their 3 dB photo-response bandwidths are around 23 GHz. Their applications will further improve the performances of the optical interconnects

       PDF全文 (下载：6)        Chinese Optics Letters ，2019年第17卷第4期 pp.04      

Zhu Lida   Wang Yi   Yuan Yi   Zhou Hongxian   Zhao Yuqian   Ma Zhenhe  

      摘要 + ：(浏览：45次) | 此论文可免费阅读 (可能需要登录)

We demonstrated a method for CCT measurement with a sub-micrometer sensitivity using a spectral domain optical coherence tomography (SD-OCT) system without needing a super broad bandwidth light source. By combining the frequency and phase components of Fourier transform (FT), the method is capable of measurement of a large dynamic range with a high sensitivity. Absolute phases are retrieved by comparing the correlations between the detected and simulated interference fringes. The phase unwrapping ability of the present method was quantitatively tested by measuring the displacement of a piezo linear stage. The human CCTs of six volunteers were measured to verify its clinical application. It provides a potential tool for clinical diagnosis and research applications in ophthalmology.

       PDF全文 (下载：3)        Chinese Optics Letters ，2019年第17卷第4期 pp.04      

chen minghui   jia wenyu   he jintao   geiser martial   zheng gang  

      摘要 + ：(浏览：49次) | 此论文可免费阅读 (可能需要登录)

This study introduced the research into, and development of, a portable, miniaturised system for the measurement of the refractive index of sub-microlitre liquid based on a microfluidic chip. A technical method, namely, double-beam interference, was proposed for use in the measurement. Based on this, by using a laser diode as a light source, changes in refractive index were calculated by utilising a complementary metal-oxide-semiconductor (CMOS) to detect the movement of interference fringes of the liquid. Firstly, this study simulated the effects of influencing factors on the interference infringes of two Gaussian beams, such as their spot sizes, distance between two beam spots, and detection range. Secondly, this research introduced the system design and construction of the double-beam interference method and analysed the results of refractive index tests on sub-microlitre aqueous glucose solutions with different concentrations therewith. The measurement accuracy reached 10-4 RIU. This system has a compact structure and is rendered portable by using batteries for its power supply. The entire system is designed to be a double Z-shaped structure with a length of about 15 cm, a width of 5 cm, and height of about 10 cm: it can be used to measure changes in refractive index of sub-microlitre to nanolitre liquids based on the use of a microfluidic chip.

       PDF全文 (下载：2)        Chinese Optics Letters ，2019年第17卷第4期 pp.04      

Guo Yujian   Alkhazragi Omar   Kang Chun   SHEN CHAO   Mao Yuan   Sun Xiaobin   Ng Tien   Ooi B. S.  

      摘要 + ：(浏览：41次) | 此论文可免费阅读 (可能需要登录)

This tutorial focuses on devices and technologies that are part of laser-based visible light communication (VLC) systems. Laser-based VLC systems have advantages over their light-emitting-diode-based counterparts, including having high transmission speed and long transmission distance. We summarize terminologies related to laser-based solid-state lighting and VLC, and further review the advances in device design and performance. The high-speed modulation characteristics of laser diodes and superluminescent diodes, the on-chip integration of optoelectronic components in the visible color regime, such as the high-speed integrated photodetector, were introduced. The modulation technology for laser-based white light communication systems, and the challenges for future development were then discussed.

       PDF全文 (下载：6)        Chinese Optics Letters ，2019年第17卷第4期 pp.04      

Chen Menglin   Luo Zhijun   Liu Yanan   Gan Zongsong  

      摘要 + ：(浏览：41次) | 此论文可免费阅读 (可能需要登录)

Fractional density of states (FDOS) hinders the accurate measuring of the overall spontaneous emission (SE) control ability of a three-dimensional (3D) photonic crystal (PC) with the current widely used SE decay lifetime measurement systems. Based on analyzing the FDOS property of a 3D PC from theory and simulation, the excitation focal spot position averaged FDOS with a distribution broadening parameter were proposed to accurately reflect the overall SE control ability of the 3D PC. Experimental work was done to confirm that our proposal is effective which can contribute to comprehensively characterize the SE control performance of photonic devices with quantified parameters.

       PDF全文 (下载：1)        Chinese Optics Letters ，2019年第17卷第4期 pp.04      

Yan Wen   Yao Yuan   Sun Yuxin   Hoyt Chad   Jiang Yanyi   Ma Longsheng  

      摘要 + ：(浏览：47次) | 此论文可免费阅读 (可能需要登录)

We study a Zeeman slower using the magnetic field generated by a coil pair for a magneto-optical trap. The efficiency of the Zeeman slower is shown to be dependent on the intensity and the frequency detuning of the laser light for slowing the atoms. With the help of numerical analysis, optimal experimental parameters are explored. Experimentally, the optimal frequency detuning and intensity of the slowing beam are explored, and 4.2 × 107 ytterbium atoms are trapped in the magneto-optical trap.

       PDF全文 (下载：1)        Chinese Optics Letters ，2019年第17卷第4期 pp.04      

Ge Aichen   Liu Bowen   Chen Wei   Tian Haochen   Song Youjian   Chai Lu   Hu Minglie  

      摘要 + ：(浏览：44次) | 此论文可免费阅读 (可能需要登录)

We demonstrate a coherent synthesis system based on femtosecond Yb-doped fiber laser technology. The output pulse of the amplification system is divided into two replicas, and seeded into photonic crystal fibers of two parallel branches for nonlinear pulse compression. Because of the different nonlinear dynamics in the photonic crystal fibers, the compressed pules show different spectra which can be spliced to form a broad coherent spectrum. The integrated timing jitter between the pulses of two branches is less than one tenth of an optical cycle. By coherently synthesizing pulses from these two branches, 8-fs few-cycle pulses are produced.

       PDF全文 (下载：1)        Chinese Optics Letters ，2019年第17卷第4期 pp.04      

Shang Jimin   Zhang Shuai   Wang Yongqiang   Wen Hongyu   Wei Zhongming  

      摘要 + ：(浏览：47次) | 此论文可免费阅读 (可能需要登录)

The electronic and optical properties of the ZrS2/SnS2 van der Waals heterostructure have been investigated. We find out the formed heterostructure has an intrinsic type-I band alignment. Moreover, the characteristics of optical absorption in heterostructure can be enhanced to the amount of 10^6 in ultraviolet light region. In addition, the tuning electronic properties of ZrS2/SnS2 heterostructure are very interesting, due to the transitions from type-I to type-II band alignment can be occurred by applying an external electric field. These results suggest that the atomically thin materials ZrS2/SnS2 heterostructure will be utilized for the flexible optoelectronic applications.

       PDF全文 (下载：7)        Chinese Optics Letters ，2019年第17卷第2期 pp.02      

wang taijin   wang jiang   Wang Yonggang   yang xiguang   liu sicong   lv ruidong   Chen Zhendong  

      摘要 + ：(浏览：42次) | 此论文可免费阅读 (可能需要登录)

A single output Q-switched Nd: GdVO4 laser with a reflective graphene oxide (GO) saturable absorber was demonstrated. The shortest pulse duration in Q-switched laser is 115 ns and the output power ranges from 1.23 W at 1.71 MHz to 2.11 W at 2.50 MHz when the pump power rises from 7.40 W to 10.90 W, with the utilization of GO Langmuir-Blodgett (LB) films based on the convenient and low-cost LB technique. To the best of our knowledge, It’s the highest output power in Q-switched laser with GO saturable absorber.

       PDF全文 (下载：3)        Chinese Optics Letters ，2019年第17卷第2期 pp.02      

Yang Huashan   Zhang Fuling   Leng Lemeng   Zeng Zhaobang   Shao Yue   Zhang Hui   Yang Nan   Chen Xiangning  

      摘要 + ：(浏览：41次) | 此论文可免费阅读 (可能需要登录)

A simple method improving grating couplers’ coupling efficiency without any extra micro fabrication processes is proposed. This method can improve the coupling efficiency with 1.69dB by utilizing the combined interference in cladding layer and air gap between the cladding surface and the paralleled angle polished fiber facet. The proposed method can be applied to various kinds of on-chip grating couplers. Back reflection, 1-dB bandwidth and fiber alignment tolerance has been also improved at the same time.

       PDF全文 (下载：5)        Chinese Optics Letters ，2019年第17卷第3期 pp.03