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Design of supercontinuum generating photonic crystal fiber at 1.06, 1.31 and 1.55 µm wavelengths for medical imaging and optical transmission systems  [PDF]
Feroza Begum, Yoshinori Namihira
Natural Science (NS) , 2011, DOI: 10.4236/ns.2011.35054
Abstract: We propose broad supercontinuum spectrum generating highly nonlinear photonic crystal fiber (HN-PCF) which can be used in ultrahigh- resolution optical coherence tomography and optical transmission systems. Using full vector finite difference method, we investigated the different properties of HN-PCF. Broadband su-percontinuum spectrum is numerically calculated by using nonlinear Schr?dinger equation. Investigation showed that it is possible to obtain longitudinal resolution in a biological tissue of 1.3 μm, 1.2 μm and 1.1 μm by using picosecond continuum light at center wavelengths of 1.06 μm, 1.31 μm and 1.55 μm, respectively.
1.55 μm Low-temperature-grown GaAs Resonant Cavity Enhanced Photodetector
1.55 μm低温生长GaAs谐振腔增强型探测器

Han Qin,Peng Hongling,Du Yun,Ni Haiqiao,Zhao Huan,Niu Zhichuan,Wu Ronghan,

光子学报 , 2006,
Abstract: 利用低温(200℃)生长的GaAs材料作为吸收层制备了GaAs基1.55μm谐振腔增强型(RCE)光电探测器,对其光电特性进行了分析、研究·无光照0偏压下探测器暗电流为8.0×10-12A;光电流谱峰值波长1563nm;响应谱线半宽4nm,具有良好的波长选择性·
The Fabrication of Low Cost Si-based Continuously Tunable 1.55μm RCE Photodetector
硅基1.55 μm可调谐共振腔窄带光电探测器的研究

State Key Joint Laboratory of Integrated Optoelectronics,

光子学报 , 2005,
Abstract: A novel method for fabricating low cost Si-based continuously tunable long wavelength resonant cavity enhanced (RCE) photodetectors was reported,in which InGaAs epitaxy layers were bonded to silicon substrates without any special treatment on bonding surfaces,employing the silicate gel as bonding medium.A thermally tunable Si-based InGaAs RCE photodetector operating at 1.3~1.6 μm was obtained,with a quantum efficiency of about 44% at the resonant wavelength of about 1.5 μm and a FWHM of about 12.5 nm.A tuning range of 14.5 nm and a 3 dB bandwidth of 1.8 GHz were obtained. This device was fabricated with traditional processes,thus the cost was decreased. It demonstrates a great potential for industry processes.
Low Threshold Distributed Feedback Quantum Cascade Lasers with Widely Spaced Emission Wavelengths
LI Yao-Yao,XU Gang-Yi,LI Ai-Zhen,WEI Lin,LI Hua,MEI Bin,

中国物理快报 , 2007,
Abstract: We report lasing properties of distributed feedback quantum cascade lasers (DFB QCLs) including a doublephonon-resonance active region, at wavelength of about 8.4 μm. A broad gain spectrum is generated due to the coupling between the lower laser level in the active region and the levels in the injector, and is demonstrated by the lasing spectrum of the corresponding Fabry-Perot QCLs whose width is 0.5 μm at 1.5 times of the threshold current. As a result, the DFB QCLs employing different grating periods exhibit a wavelength span of 0.18μm at room temperature and total wavelength coverage of 0.28μm at various heat sink temperatures. A high side mode suppression ratio of about 30dB and a low threshold current density of 1.78kA/cm^2 are achieved as the lasers operate at room temperature in pulsed mode.
ZnO UV photodetector with controllable quality factor and photosensitivity  [PDF]
Leonardo C. Campos,Marcos H. D. Guimaraes,Alem-Mar B. Goncalves,Sergio de Oliveira,Rodrigo G. Lacerda
Physics , 2013, DOI: 10.1063/1.4790633
Abstract: ZnO nanowires have an enormous potential for applications as ultra-violet (UV) photodetectors. Their mechanism of photocurrent generation is intimately related with the presence of surface states where considerable efforts, such as surface chemical modifications, have been pursued to improve their photodetection capabilities. In this work, we report a step further in this direction demonstrating that the photosensitivity and quality factor (Q factor) of the photodetector are entirely tunable by an applied gate voltage. This mechanism enables UV photodetection selectivity ranging from wavelengths from tens of nanometers (full width at half maximum - FWHM) down to a narrow detection of 3 nm. Such control paves the way for novel applications, especially related to the detection of elements that have very sharp luminescence.
On-chip integrated, silicon-graphene plasmonic Schottky photodetector, with high responsivity and avalanche photogain  [PDF]
Ilya Goykhman,Ugo Sassi,Boris Desiatov,Noa Mazurski,Silvia Milana,Domenico de Fazio,Anna Eiden,Jacob Khurgin,Joseph Shappir,Uriel Levy,Andrea C. Ferrari
Physics , 2015,
Abstract: We report an on-chip integrated metal-graphene-silicon plasmonic Schottky photodetector with 85mA/W responsivity at 1.55 um and 7% internal quantum efficiency. This is one order of magnitude higher than metal-silicon Schottky photodetectors operated in the same conditions. At a reverse bias of 3V, we achieve avalanche multiplication, with 0.37A/W responsivity and avalanche photogain~2. This paves the way to graphene integrated silicon photonics.
Ultrasensitive and broadband MoS2 photodetector driven by ferroelectrics  [PDF]
Xudong Wang,Peng Wang,Jianlu Wang,Weida Hu,Xiaohao Zhou,Nan Guo,Hai Huang,Shuo Sun,Hong Shen,Tie Lin,Minghua Tang,Lei Liao,Anquan Jiang,Jinglan Sun,Xiangjian Meng,Xiaoshuang Chen,Wei Lu,Junhao Chu
Physics , 2015, DOI: 10.1002/adma.201503340
Abstract: Photodetectors based on two dimensional materials have attracted growing interest. However, the sensitivity is still unsatisfactory even under high gate voltage. Here we demonstrate a MoS2 photodetector with a poly(vinylidene fluoride-trifluoroethylene) ferroelectric layer in place of the oxide layer in a traditional field effect transistor. The dark current of the photodetector is strongly suppressed by ferroelectric polarization. A high detectivity 2.21012 Jones) and photoresponsitivity (2570 A W) detector has been achieved under ZERO gate bias at a wavelength of 635 nm. Most strikingly, the band gap of few-layer MoS2 can be tuned by the ultra-high electrostatic field from the ferroelectric polarization. With this characteristic, photoresponse wavelengths of the photodetector are extended into the near infrared (0.85-1.55m). A ferroelectrics optoelectronics hybrid structure is an effective way to achieve high performance 2D electronic optoelectronic devices.
Development of an Amorphous Selenium-Based Photodetector Driven by a Diamond Cold Cathode  [PDF]
Tomoaki Masuzawa,Ichitaro Saito,Takatoshi Yamada,Masanori Onishi,Hisato Yamaguchi,Yu Suzuki,Kousuke Oonuki,Nanako Kato,Shuichi Ogawa,Yuji Takakuwa,Angel T. T. Koh,Daniel H. C. Chua,Yusuke Mori,Tatsuo Shimosawa,Ken Okano
Sensors , 2013, DOI: 10.3390/s131013744
Abstract: Amorphous-selenium (a-Se) based photodetectors are promising candidates for imaging devices, due to their high spatial resolution and response speed, as well as extremely high sensitivity enhanced by an internal carrier multiplication. In addition, a-Se is reported to show sensitivity against wide variety of wavelengths, including visible, UV and X-ray, where a-Se based flat-panel X-ray detector was proposed. In order to develop an ultra high-sensitivity photodetector with a wide detectable wavelength range, a photodetector was fabricated using a-Se photoconductor and a nitrogen-doped diamond cold cathode. In the study, a prototype photodetector has been developed, and its response to visible and ultraviolet light are characterized.
Graphene as a Novel Single Photon Counting Optical and IR Photodetector  [PDF]
J. O. D. Williams,J. S. Lapington,M. Roy,I. B. Hutchinson
Physics , 2015, DOI: 10.1049/ic.2015.0002
Abstract: Bilayer graphene has many unique optoelectronic properties , including a tuneable band gap, that make it possible to develop new and more efficient optical and nanoelectronic devices. We have developed a Monte Carlo simulation for a single photon counting photodetector incorporating bilayer graphene. Our results show that, conceptually it would be feasible to manufacture a single photon counting photodetector (with colour sensitivity) from bilayer graphene for use across both optical and infrared wavelengths. Our concept exploits the high carrier mobility and tuneable band gap associated with a bilayer graphene approach. This allows for low noise operation over a range of cryogenic temperatures, thereby reducing the cost of cryogens with a trade off between resolution and operating temperature. The results from this theoretical study now enable us to progress onto the manufacture of prototype photon counters at optical and IR wavelengths that may have the potential to be groundbreaking in some scientific research applications.
Zinc Oxide Nanoparticle Photodetector
Sheng-Po Chang,Kuan-Jen Chen
Journal of Nanomaterials , 2012, DOI: 10.1155/2012/602398
Abstract: A zinc oxide (ZnO) nanoparticle photodetector was fabricated using a simple method. Under a 5 V applied bias, its dark current and photocurrent were 1.98×10?8 and 9.42×10?7 A, respectively. In other words, a photocurrent-to-dark-current contrast ratio of 48 was obtained. Under incident light at a wavelength of 375 nm and a 5 V applied bias, the detector’s measured responsivity was 3.75 A/W. The transient time constants measured during the turn-ON and turn-OFF states were ON=204s and OFF=486s, respectively.
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