Author Affiliations
Abstract
1 Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, and Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215123, China
2 Department of Materials Science and Engineering, Monash University, Clayton 3800, Australia
Black phosphorus (BP) is a promising material for ultrafast and broadband photodetection because of its narrow bandgap from 0.35 eV (bulk) to 1.8 eV (monolayer) and high carrier mobility. Although photodetectors based on BP with different configurations have been reported, high photosensitivity was mostly observed in the visible range. A highly efficient BP-based infrared photodetector operated in the telecom spectral range, especially at 1550 nm, has not been demonstrated. Here, we report a Schottky-type photodetector based on thin BP flakes, operating in a broad spectral range from visible (635 nm) to infrared (1550 nm). A responsivity as high as 230 A·W 1 was achieved at 1550 nm with a source-drain bias of 1 V. The rise time is 4.8 ms, and the fall time is 6.8 ms. Under light illumination and external bias, the Schottky barrier between the BP and metal was reduced, leading to efficient photocurrent extraction. The unprecedented performance of the BP photodetector indicates intriguing potential for sensing, imaging, and optical communication.
040.5160 Photodetectors 160.1890 Detector materials Chinese Optics Letters
2018, 16(2): 020002
Author Affiliations
Abstract
1 Laboratory of Nanotechnology and Microsystems, Mechanical Engineering College, Shijiazhuang 050000, China
2 State Key Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Science, Beijing 100084, China
Short-wave infrared (SWIR) detectors combining AlAs/In0.53Ga0.47As/AlAs double barrier structure (DBS) with In0.53Ga0.47As absorption layer are fabricated by molecular beam epitaxy. By adding a p-charge layer, the dark current density of the detector is lowered by 3 orders of magnitude. The responsivity of the detector is tested at room temperature, which reaches 6000 A/W when the power of the incident light is 0.7 nW. The noise equivalent power (NEP) of the detector at 5 kHz is measured to be 3.77×10 14 W/Hz1/2 at room temperature.
250.0040 Detectors 230.5160 Photodetectors 160.1890 Detector materials 060.5565 Quantum communications Chinese Optics Letters
2016, 14(2): 022501
Author Affiliations
Abstract
1 Institute of Optoelectronics Technology, China Jiliang University, Hangzhou 310018, China
2 School of Electronic and Optical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
Using the first-principles method based on the density functional theory (DFT), the work function of seven different GaN (0001) (1×1) surface models is calculated. The calculation results show that the optimal ratio of Cs to O for activation is between 3∶1 and 4∶1. Then, Cs/O activation and stability testing experiments on reflection-mode negative electron affinity GaN photocathodes are performed. The surface model [GaN (Mg): Cs] Cs-O after being activated with cesium and oxygen is used. The experiment results illustrate that the adsorption of O contained in the residual gas increases the surface potential barrier and the reduction of the effective dipole quantity is the basic cause of the quantum efficiency decay.
040.7190 Ultraviolet 160.1890 Detector materials 230.0040 Detectors 260.7210 Ultraviolet, vacuum Chinese Optics Letters
2015, 13(10): 100401
Author Affiliations
Abstract
Surface photovoltage spectroscopy equations for cathode materials with an AlxGa1 xAs buffer layer are determined in order to effectively measure the body parameters for transmission-mode (t-mode) photocathode materials before Cs-O activation. Body parameters of cathode materials are well fitted through experiments and fitting calculations for the designed AlxGa1 xAs/GaAs structure material. This investigation examines photo-excited performance and measurements of body parameters for t-mode cathode materials of different doping structures. It also helps study various doping structures and optimize structure designs in the future.
040.7190 Ultraviolet 160.1890 Detector materials 230.0040 Detectors 260.7210 Ultraviolet, vacuum Chinese Optics Letters
2012, 10(11): 110401
Author Affiliations
Abstract
1 Key Laboratory of Optoelectronic Technology and Systems of Ministry of Education of China, College of Optoelectronic Engineering, Chongqing University, Chongqing 400044, China
2 Institute of Electronic Engineering and Opto-Electric Technology, Nanjing University of Science and Technology, Nanjing 210094, China
We create a GaN photocathode based on graded AlxGa1?xN buffer layers to overcome the influence of buffer-emission layer interface on the photoemission of transmission-mode GaN photocathodes. A gate-shaped spectral response with a 260-nm starting wavelength and a 375-nm cut-off wavelength is obtained. Average quantum efficiency is 15% and short wavelength responses are almost equivalent to long wavelength ones. The fitted interface recombination velocity is 5×104 cm/s, with negligible magnitude, proving that the design of the graded buffer layers is efficient in obtaining good interface quality between the buffer and the emission layer.
紫外探测器 GaN 光电阴极 缓冲层 界面复合速率 光电发射 040.7190 Ultraviolet 160.1890 Detector materials 230.0040 Detectors 260.7210 Ultraviolet, vacuum Chinese Optics Letters
2011, 9(1): 010401
Author Affiliations
Abstract
1 Department of Physics, Fudan University, Shanghai 200433
2 Department of Optical Science and Engineering, State Key Lab of Advanced Photonic Materials and Devices, Fudan University, Shanghai 200433
3 National Laboratory for Infrared Physics, Chinese Academy of Sciences, Shanghai 200083
The Langmuir-Blodgett (LB) films of hemicyanine dyes were prepared by LB technique. The films showed pyroelectric effect. The pyroelectric coefficient measured by the method of integrated charges was 12 'mu'C/(m2K) at room temperature, and the relationship between the orientation of DAEP dye in the films and temperature was studied by polarized Fourier transform infrared spectroscopy (FTIR) spectroscopy and second harmonic generation (SHG). It was indicated that the observed pyroelectricity can be ascribed preliminarily to the structure modification of the polar head groups and the deterioration of the film framework (the first-order phase transition) resulted in the change of spontaneous polarization with temperature.
190.4710 Optical nonlinearities in organic materials 300.6340 Spectroscopy, infrared 190.2620 Frequency conversion 040.3060 Infrared 160.1890 Detector materials Chinese Optics Letters
2005, 3(0s): 68
Author Affiliations
Abstract
1 School for Information and Opto-Electronic Science and Engineering, South China Normal University, Guangzhou 510631
2 Department of Applied Physics, South China University of Technology, Guangzhou,510641
3 College of Applied Physics, Guangdong University of Technolody, Guangzhou 510090
The passively quenched operation of avalanche photodiode (APD) has been used to characterizing InGaAs/InP APD including punch through voltage, avalanche voltage and break down voltage that are all important in the design of APD for single photon detection. The punch through voltage at certain doping level can be related to the thickness of the InP multiplication layer and the thickness of the un-intentionally doped n-type InP layer can be adjusted in according to the experimental data. The analysis indicates that the punch through voltage should be close to the breakdown voltage that can be realized by adjusting the thickness of InP multiplication layer.
040.3060 Infrared 040.3780 Low light level 040.5570 Quantum detectors 160.1890 Detector materials 230.5160 Photodetectors 270.5570 Quantum detectors Chinese Optics Letters
2005, 3(0s): 31
Author Affiliations
Abstract
1 Department of Control Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074
2 Department of Optoelectronic Engineering, Huazhong University of Science and Technology, Wuhan 430074
3 Institute for Pattern Recognition and Artificial Intelligence, Huazhong University of Science and Technology, Wuhan 430074
A novel nanopolycrystalline structure of vanadium dioxide thin films is deposited on silicon or fused silica substrates by reactive ion sputtering and followed by an annealing. The characteristic analysis shows that the films have a columnar nanostructure with an average grain of 8 nm. The resistivities as a function of ambient temperatures tested by four-point probes for as-deposited films present that the transition temperature for nanostructure of vanadium dioxide films is near 35 Celsius degree which lowers about 33 Celsius degree in comparison with the transition temperature at 68 Celsius degree in its microstructure.
310.0310 thin films 160.6840 thermo-optical materials 160.1890 detector materials 350.5030 phase Chinese Optics Letters
2005, 3(12): 12719
Author Affiliations
Abstract
State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 300072
Semiconductor fiber temperature sensors have been used widely in many fields, but most of them pick up temperature by measuring the optical intensity of certain fixed narrow-band in absorption spectrum. Furthermore, they are sensitive to the loss of optical intensity and the fluctuation of light source power. The novel temperature measurement system proposed in this paper is based on the semiconductor absorption theory and the spectral analysis of method. To measure temperature, the sensor model detects not the certain narrow-band spectrum but the most spectra of the optical absorption edge. Therefore the measurement accuracy and the stability can be improved greatly. Experimental results are in agreement with theoretical analysis results perfectly.
120.6780 temperature 160.1890 detector materials 040.1520 CCD charge-coupled device Chinese Optics Letters
2004, 2(4): 04220
