Current Issue : April - June Volume : 2015 Issue Number : 2 Articles : 5 Articles
A comparative study is presented between Bragg grating (FBG) and polarimetric sensors (PS), two of the most promising fiber\noptic sensing techniques for the structural health monitoring of smart materials based on carbon fiber composites. The paper\ndescribes the realization of a test plate equippedwith both types of sensors and reports the characterization under static and dynamic\nconditions, highlighting pros and cons of both technologies. The FBG setup achieves 1.15 �± 0.0016 pm/kg static load response and\nreproduces dynamic excitation with 0.1% frequency uncertainty; the PS system exhibits a sensitivity of 1.74 �± 0.001mV/kg and\nreproduces dynamic excitation with 0.5% frequency uncertainty. It is shown that the PS technology is a good and cheap alternative\nto FBG for vibration-monitoring of small structures at high frequency....
During the last decades the development of laser cooling and trapping has revolutionized the field of quantumoptics.Nowwemaster\ntechniques to control the quantum properties of atoms and light, even at a single atom and single photon level. Understanding and\ncontrolling interactions of atoms and light both on the microscopic single particle and on the macroscopic collective levels, are two\nof the very active directions of the current research in this field.The goal is to engineer quantum systems with tailored properties\ndesigned for specific applications. One of the ambitious applications on this way is interfacing quantum information for quantum\ncommunication and quantum computing. We summarize here theoretical ideas and experimental methods for interfacing at om based\nquantum memories with single flying photons....
Haidinger�s brush, an entoptic phenomenon, is very useful in checking central vision loss and eccentric fixation. Haidinger�s brush\nis also used to provide vision training for subjects affected by eccentric fixation/lazy eye.We propose the use of Haidinger�s brush\nfor mass self-screening of vision in cinema the atres in one go and at no cost to the subjects. We also suggest a simple projection\ntechnology for mass vision screening of subjects in waiting rooms or at shop windows of eye-care practitioners. Finally, we propose\na new affordable handheld device for vision training. The test and the devices that we propose would increase public awareness of\neye health, improve vision in children, and help prevent blindness in the elderly....
All-optical logic XNOR gate is realized by a series combination of XOR and INVERT gates. This Boolean function is realized by\nusingMach-Zehnder interferometers (MZIs) and exploiting the nonlinear effect of two-photon absorption (TPA) in semiconductor\noptical amplifiers (SOAs).Theemployed model takes into account the impact of amplified spontaneous emission (ASE), input pulse\nenergy, pulsewidth, SOAs carrier lifetime, and linewidth enhancement factor (????-factor) on the gate�s output quality factor (Q-factor).\nThe outcome of this study shows that the all-optical XNOR gate is indeed feasible with the proposed scheme at 250 Gb/s with both\nlogical correctness and acceptable quality...
Radio luminescence optical fibre sensors are gaining importance since these devices are promising in several applications like high\nenergy physics, particle tracking, real-time monitoring of radiation beams, and radioactive waste. Silica optical fibres play an\nimportant role thanks to their high radiation hardness. Moreover, rare earths may be incorporated to optimise the scintillation\nproperties (emission spectrum, decay time) according to the particular application. This makes doped silica optical fibres a very\nversatile tool for the detection of ionizing radiation in many contexts. Among the fields of application of optical fibre sensors,\nradiation therapy represents a driving force for the research and development of new devices. In this review the recent progresses\nin the development of rare earth doped silica fibres for dosimetry in the medical field are described. After a general description\nof advantages and challenges for the use of optical fibre based dosimeter during radiation therapy treatment and diagnostic\nirradiations, the features of the incorporation of rare earths in the silica matrix in order to prepare radio luminescent optical fibre\nsensors are presented and discussed. In the last part of this paper, recent results obtained by using cerium, europium, and ytterbium\ndoped silica optical fibres in radiation therapy applications are reviewed....
Loading....