Author Affiliations
Abstract
1 Laboratory of Micro-Nano Photonic and Optoelectronic Materials and Devices, Key Laboratory of Materials for High-Power Laser, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
3 State Key Laboratory of Surface Physics, Key Laboratory of Micro and Nano Photonic Structures of Ministry of Education, Department of Physics, Collaborative Innovation Center of Advanced Microstructures, Fudan University, Shanghai 200433, China
4 Department of Physics, Engineering Physics & Astronomy and Department of Chemistry, Queen’s University, Kingston K7L-3N6, Ontario, Canada
5 State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
Mechanical exfoliation (ME) and chemical vapor deposition (CVD) MoS2 monolayers have been extensively studied, but the large differences of nonlinear optical performance between them have never been clarified. Here, we prepared MoS2 monolayers using ME and CVD methods and investigated the two-photon absorption (TPA) response and its saturation. We found that the TPA coefficient of the ME monolayer was about (1.88 ± 0.21) × 103 cm/GW, nearly two times that of the CVD one at (1.04 ± 0.15) × 103 cm/GW. Furthermore, we simulated and compared the TPA-induced optical pulse modulation in multilayer cascaded structures, which is instructive and meaningful for the design of optical devices such as a beam shaper and optical limiter.
190.4400 Nonlinear optics, materials 160.4236 Nanomaterials 190.5970 Semiconductor nonlinear optics including MQW 020.4180 Multiphoton processes Chinese Optics Letters
2019, 17(8): 081901
Author Affiliations
Abstract
1 Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
2 University of Chinese Academy of Sciences, Beijing 100049, China
With the development of semiconductor technology, semiconductor laser devices and semiconductor laser pump solid-state laser devices have been widely applied in z-scan experiments. However, the feedback light-induced output instability of semiconductor laser devices can negatively affect the accurate testing of the nonlinear index. In this work, the influence of feedback light on z-scan measurement is analyzed. Then the calculated formula of feedback light-induced false nonlinear z-scan curves is theoretically derived and experimentally verified. Two methods are proposed to reduce or eliminate the feedback light-induced false nonlinear effect. One is the addition of an attenuator to the z-scan optical path, and the other is the addition of an opto-isolator unit to the z-scan setup. The experimental and theoretical results indicate that the feedback light-induced false nonlinear effect is markedly reduced and can even be ignored if appropriate parameters are chosen. Thus, theoretical and experimental methods of eliminating the negative effect of feedback light on z-scan measurement are useful for accurately obtaining the nonlinear index of a sample.
Nonlinear optics Semiconductor nonlinear optics including MQW Photonics Research
2014, 2(2): 02000051
Author Affiliations
Abstract
School of Information Science and Technology, Southwest Jiaotong University, Chengdu 610031,China
A tunable slow light of 2.5-Gb/s pseudo-random binary sequence signal using a 1550-nm vertical-cavity surface-emitting laser (VCSEL) is experimentally demonstrated. The influences of the bias current and the gain saturation on the slow light are investigated. With bias current increasing, tunable optical group delay up to 98 ps is obtained at room temperature. Demonstration of the time delay between 16 and 24 ps by signal intensity change is reported. Under an appropriate bias current, by tuning the input signal to track the peak gain wavelength of the VCSEL, slow light of a power penalty as low as 1 dB is achieved. With such a low power penalty, the VCSEL has a great potential application as a compact optical buffer.
慢光 垂直腔面发射激光器 增益饱和 功率罚 140.7260 Vertical cavity surface emitting lasers 210.4680 Optical memories 190.5970 Semiconductor nonlinear optics including MQW Chinese Optics Letters
2011, 9(5): 051401
Author Affiliations
Abstract
State Key Laboratory on Integrated Optoelectronics, National Laboratory for Superlattices and Microstructures, Institute of Semiconductor, Chinese Academy of Sciences, Beijing 100083
Continuous wave operation of a semiconductor laser diode based on five stacks of InAs quantum dots (QDs) embedded within strained InGaAs quantum wells as an active region is demonstrated. At room temperature, 355-mW output power at ground state of 1.33-1.35 microns for a 20-micron ridge-waveguide laser without facet coating is achieved. By optimizing the molecular beam epitaxy (MBE) growth conditions, the QD density per layer is raised to 4*10^(10) cm^(-2). The laser keeps lasing at ground state until the temperature reaches 65 Celsius degree.
160.6000 Semiconductors, including MQW 140.5960 Semiconductor lasers Chinese Optics Letters
2006, 4(7): 413
Author Affiliations
Abstract
College of Science, Zhejiang University of Science and Technology, Hangzhou 310023
A novel InGaAs/InAlAs coupled quantum well structure is proposed for large field-induced refractive index change with low absorption loss. In the case of low applied electric field of 15 kV/cm and low absorption loss ('alpha' <= 100 cm^(-1)), a large field-induced refractive index change (for transverse electric (TE) mode, 'Delta' n = 0.012; for transverse magnetic (TM) mode, 'Delta' n = 0.0126) is obtained in the structure at the operation wavelength of 1.55 um. The value is larger by over one order of magnitude than that in a rectangular quantum well. The result is very attractive for semiconductor optical switching devices.
230.0230 Optical devices 160.6000 Semiconductors, including MQW 190.5970 Semiconductor nonlinear optics including MQW 160.4760 Optical properties Chinese Optics Letters
2006, 4(6): 351
Author Affiliations
Abstract
1 National Key Laboratory of Tunable Laser Technology, Institute of Opto-Electronics, Harbin Institute of Technology, Harbin 150001
2 Shenyang Normal University, Shenyang 110034
3 College of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093
The third-order nonlinearities of PbS nano-belts have been investigated using the Z-scan technique with nanosecond laser pulses at 532 nm. The effect of the PbS semiconductor nano-belt size on the third-order optical nonlinearities and optical limiting properties was studied. We found that the nonlinear absorption and nonlinear refraction have not strict dependence on the nano-belt size under our investigated condition, but their optical limiting behavior is different. The optical limiting mechanism of materials is discussed.
190.3970 Microparticle nonlinear optics 190.4400 Nonlinear optics, materials 190.5970 Semiconductor nonlinear optics including MQW Chinese Optics Letters
2005, 3(0s): 248
Author Affiliations
Abstract
1 School of Science, Beijing University of Posts and Telecommunications, Beijing 100876
2 Key Laboratory of Communication Lightwave Technologies, Ministry of Education, Beijing 100876
We systematically investigate a strain of self-assembled InAs/GaAs quantum dots (QDs) for the case of growth on a (001) substrate. The dependence of the biaxial and hydrostatic components of the strain on the quantum dot aspect ratio is studied using a finite element method. The dependence of the carrier's confining potentials is then calculated in the framework of eight-band kp theory. The shifts of the energy level in three shapes of QDs are investigated. By comparing the results, the influence of the strain on the QDs are given.
160.6000 Semiconductors, including MQW 130.5990 Semiconductors 140.5960 Semiconductor lasers 160.3380 Laser materials Chinese Optics Letters
2005, 3(0s): 244
Author Affiliations
Abstract
1 College of Optics and Electrorics Engineering, University of Shanghai for Science and Technology , Shanghai 200093
2 Department of Physics, Jining Medical College, Jining 272013
3 College of Physics, Qufu Normal University, Qufu 273165
ZnO is an n-type semiconductor having a hexagonal wurtzite structure. By X-ray diffraction (XRD) and scanning electron microscope (SEM), the influences of substrate temperature, the ratio of Ar to O2 and thermal temperature on ZnO crystal quality were studied. The results show that ZnO films deaposited at substrate temperature of 240 Celsius degrees and Ar:O2=1:3 have the best crystallization. UV photoluminescence is observed when ZnO films are excited by He-Cd laser at room temperature. Stress at boundary causes an intrinsic UV emission peak shift to the lower energy. Oxygen vacancy or zinc interstitial causes deep-level emission. With higher substrate temperature, the crystallization is improved and the stress and deep-level green emission are reduced.
300.6190 Spectrometers 250.5230 Photoluminescence 160.6000 Semiconductors, including MQW 310.0310 Thin films 110.7440 X-ray imaging Chinese Optics Letters
2005, 3(0s): 242
Author Affiliations
Abstract
1 Department of Physics, National University of Singapore, Singapore 117542, Republic of Singapore
2 Institute of Bioengineering and Nanotechnology, Singapore 138669, Republic of Singapore
We report direct measurements of both magnitude and spectral dispersion of two-photon absorption in organic-capped CdSe quantum dots and three-photon absorption in organic-capped ZnO quantum dots by the use of open-aperture Z-scan technique with femtosecond laser pulses in the wavelength range of 720-950 nm. We find that these nonlinear coefficients are at least an order of magnitude greater than their bulk counterparts. Our experimental data are compared with theories and the rules for wavelength scaling are discussed.
190.4180 Multiphoton processes 190.4400 Nonlinear optics, materials 190.4720 Optical nonlinearities of condensed matter 190.5970 Semiconductor nonlinear optics including MQW Chinese Optics Letters
2005, 3(0s): 203
Author Affiliations
Abstract
1 State Key laboratory of Precision Measurement Technology and Instruments, Tsinghua University, Beijing 100084
2 Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083
3 Ultrafast Laser Laboratory, School of Precision Instrument and Optoelectronics Engineering, University of Tianjin, Tianjin 300072
Two semiconductor saturable absorber mirrors (SESAMs), of which one is coated with 50% reflection film on the top and the other is not, were contrastively studied in passively mode-locked solid-state lasers which were pumped by low output power laser diode (LD). Experiments have shown that reducing the modulation depth of SESAM by coating partial reflection film, whose reflectivity is higher than that between SESAM and air interface, is an effective method to get continuous wave (CW) mode-locking instead of Q-switched mode-locking (QML) in low power pumped solid-state lasers. A simple Nd:YVO4 laser pumped by low power LD, in which no water-cooling system was used, could obtain CW mode-locking by the 50% reflector coated SESAM with average output power of ~20 mW.
140.4050 mode-locked lasers 160.6000 semiconductors including MQW 140.3580 lasers solid-state Chinese Optics Letters
2005, 3(11): 11644
