Optics & Photonics - NanoScience + Engineering最新文献_第3页

Optical tweezers calibration with Bayesian inference 用贝叶斯推理标定光镊

Optics & Photonics - NanoScience + Engineering Pub Date : 2014-09-16 DOI: 10.1117/12.2064375

S. Türkcan, Maximilian U. Richly, Antoine Le Gall, Nicolas Fiszman, J. Masson, N. Westbrook, K. Perronet, A. Alexandrou

{"title":"Optical tweezers calibration with Bayesian inference","authors":"S. Türkcan, Maximilian U. Richly, Antoine Le Gall, Nicolas Fiszman, J. Masson, N. Westbrook, K. Perronet, A. Alexandrou","doi":"10.1117/12.2064375","DOIUrl":"https://doi.org/10.1117/12.2064375","url":null,"abstract":"We present a new method for calibrating an optical-tweezer setup that is based on Bayesian inference1. This method employs an algorithm previously used to analyze the confined trajectories of receptors within lipid rafts2,3. The main advantages of this method are that it does not require input parameters and is insensitive to systematic errors like the drift of the setup. Additionally, it exploits a much larger amount of the information stored in the recorded bead trajectory than standard calibration approaches. The additional information can be used to detect deviations from the perfect harmonic potential or detect environmental influences on the bead. The algorithm infers the diffusion coefficient and the potential felt by a trapped bead, and only requires the bead trajectory as input. We demonstrate that this method outperforms the equipartition method and the power-spectrum method in input information required (bead radius and trajectory length) and in output accuracy. Furthermore, by inferring a higher order potential our method can reveal deviations from the assumed second-order potential. More generally, this method can also be used for magnetic-tweezer calibration.","PeriodicalId":128143,"journal":{"name":"Optics & Photonics - NanoScience + Engineering","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121484272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Studying biofuel aerosol evaporation rates with single particle manipulation 利用单粒子操纵研究生物燃料气溶胶蒸发速率

Optics & Photonics - NanoScience + Engineering Pub Date : 2014-09-16 DOI: 10.1117/12.2061378

S. Corsetti, R. E. H. Miles, J. Reid, J. Kiefer, D. Mcgloin

{"title":"Studying biofuel aerosol evaporation rates with single particle manipulation","authors":"S. Corsetti, R. E. H. Miles, J. Reid, J. Kiefer, D. Mcgloin","doi":"10.1117/12.2061378","DOIUrl":"https://doi.org/10.1117/12.2061378","url":null,"abstract":"The significant increase in the air pollution, and the impact on climate change due to the burning of fossil fuel has led to the research of alternative energies. Bio-ethanol obtained from a variety of feedstocks can provide a feasible solution. Mixing bio-ethanol with gasoline leads to a reduction in CO emission and in NOx emissions compared with the use of gasoline alone. However, adding ethanol leads to a change in the fuel evaporation. Here we present a preliminary investigation of evaporation times of single ethanol-gasoline droplets. In particular, we investigated the different evaporation rate of the droplets depending on the variation in the percentage of ethanol inside them. Two different techniques have been used to trap the droplets. One makes use of a 532nm optical tweezers set up, the other of an electrodynamics balance (EDB). The droplets decreasing size was measured using video analysis and elastic light scattering respectively. In the first case measurements were conducted at 293.15 K and ambient humidity. In the second case at 280.5 K and a controlled environment has been preserved by flowing nitrogen into the chamber. Binary phase droplets with a higher percentage of ethanol resulted in longer droplet lifetimes. Our work also highlights the advantages and disadvantages of each technique for such studies. In particular it is challenging to trap droplets with low ethanol content (such as pure gasoline) by the use of EDB. Conversely such droplets are trivial to trap using optical tweezers.","PeriodicalId":128143,"journal":{"name":"Optics & Photonics - NanoScience + Engineering","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124529495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

GaAs-AlGaAs core-shell nanowire arrays: correlating MOVPE growth and luminescence properties GaAs-AlGaAs核壳纳米线阵列:相关MOVPE生长和发光特性

Optics & Photonics - NanoScience + Engineering Pub Date : 2014-09-16 DOI: 10.1117/12.2061816

P. Prete, Ilio Miccoli, N. Lovergine

{"title":"GaAs-AlGaAs core-shell nanowire arrays: correlating MOVPE growth and luminescence properties","authors":"P. Prete, Ilio Miccoli, N. Lovergine","doi":"10.1117/12.2061816","DOIUrl":"https://doi.org/10.1117/12.2061816","url":null,"abstract":"We report on the effects of changing the surface densities of MOVPE-grown free-standing GaAs-AlGaAs core-shell nanowires on the resulting nanostructure size and their photoluminescence (PL) properties. It is demonstrated that decreasing the local density of GaAs nanowires within the array leads to an increase of the overgrown AlGaAs shell thickness and to a substantial redshift of the nanostructure excitonic emission. Application of a vapor mass-transport limited growth model of the AlGaAs shell allows explaining the dependence of shell growth rate on nanowire density. The observed redshift of the nanowire PL emission is then experimentally correlated with these density-induced changes of the nanostructure size, namely with the nanowire shell-thickness to core-radius ratio hs/Rc. To account for a possible contribution of the nanostructure built-in elastic strain to the energy shift of the peak excitonic emission, the strain field in present core-shell nanowires was calculated as function of the nanostructure relevant geometrical parameters, based on a uniaxial elastic energy equilibrium model, and its effect on valence and conduction band shifts of the GaAs core evaluated by means of the Pikus-Bir Hamiltonian. Good agreement is obtained for hs/Rc<1, the strain-free excitonic emission being identified at 1.510 eV and ascribed to bound heavy-hole excitons. For hs/Rc>1 increasingly larger redshifts (up to ~9 meV in excess of values calculated based on the elastic strain model) are observed, and tentatively ascribed to shell-dependent exciton localization effects.","PeriodicalId":128143,"journal":{"name":"Optics & Photonics - NanoScience + Engineering","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126504174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Helicity-dependent optomechanics of chiral microparticles (presentation video) 手性微粒的螺旋相关光力学(演示视频)

Optics & Photonics - NanoScience + Engineering Pub Date : 2014-09-16 DOI: 10.1117/12.2063721

E. Brasselet, G. Tkachenko

引用次数: 0

A new technique for high sensitive detection of rotational motion in optical tweezers by a differential measurement of backscattered intensity 一种基于背散射强度差分测量的高灵敏度光镊旋转运动检测新技术

Optics & Photonics - NanoScience + Engineering Pub Date : 2014-09-16 DOI: 10.1117/12.2061245

Basudev Roy, S. Bera, A. Mondal, Ayan Banerjee

{"title":"A new technique for high sensitive detection of rotational motion in optical tweezers by a differential measurement of backscattered intensity","authors":"Basudev Roy, S. Bera, A. Mondal, Ayan Banerjee","doi":"10.1117/12.2061245","DOIUrl":"https://doi.org/10.1117/12.2061245","url":null,"abstract":"Asymmetric particles, such as biological cells, often experience torque under optical tweezers due to birefringence or unbalanced scattering forces, which makes precise determination of the torque crucial for calibration and control of the particles. The estimate of torque relies on the accurate measurement of rotational motion, which has been achieved by various techniques such as measuring the intensity fluctuations of the forward scattered light, or the polarization component orthogonal to the trapping light polarization in plasmonic nanoparticles and vaterite crystals. Here we present a simple yet high sensitive technique to measure rotation of such an asymmetric trapped particle by detecting the light backscattered onto a quadrant photodiode, and subtracting the signals along the two diagonals of the quadrants. This automatically suppresses the common mode translational signal obtained by taking the difference signal of the adjacent quadrants, while amplifying the rotational signal. Using this technique, we obtain a S/N of 200 for angular displacement of a trapped micro-rod by 5 degrees, which implies a sensitivity of 50 mdeg with S/N of 2. The technique is thus independent of birefringence and polarization properties of the asymmetric particle and depends only on the scattering cross-section.","PeriodicalId":128143,"journal":{"name":"Optics & Photonics - NanoScience + Engineering","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132561754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Investigation on resistive switching characteristics of ZnO thin film ZnO薄膜的阻性开关特性研究

Optics & Photonics - NanoScience + Engineering Pub Date : 2014-09-16 DOI: 10.1117/12.2064914

M. Wei, Fan Yang, Chunfu Li, H. Deng, G. Wen

{"title":"Investigation on resistive switching characteristics of ZnO thin film","authors":"M. Wei, Fan Yang, Chunfu Li, H. Deng, G. Wen","doi":"10.1117/12.2064914","DOIUrl":"https://doi.org/10.1117/12.2064914","url":null,"abstract":"Recently resistive switching (RS) based on ZnO thin film has attracted considerable attention since ZnO with doping can improve the switching ratio and device performance. In this work, Cu/ZnO/AZO (Al-doped ZnO) and Cu/ZnO:Cu (Cudoped ZnO) /AZO structures were fabricated for RS, using AZO as bottom electrodes due to its lattice matching with ZnO, and metal Cu was deposited as the top electrodes. The current-voltage (I-V) characteristics of these RS devices using different doped ZnO thin films as a dielectric layer were analyzed and compared. The results demonstrated that ZnO:Cu RS had a higher switching ratio and a larger range of setup and reset voltage than ZnO RS. In addition, we also found that the high resistance state（HRS）and the low resistance state (LRS) were accordance with space charge limited current (SCLC) and Ohm’s law respectively. In addition, the effect on RS performance by the top electrode was investigated by depositing top electrode with different sizes and annealing treatment, and the results indicate that the RS phenomenon occurred in these Cu/ZnO:Cu/AZO structure devices is caused by bulk effect and interfacial effect synthetically.","PeriodicalId":128143,"journal":{"name":"Optics & Photonics - NanoScience + Engineering","volume":"06 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130205385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Optical trapping of isolated mammalian chromosomes 分离哺乳动物染色体的光学捕获

Optics & Photonics - NanoScience + Engineering Pub Date : 2014-09-16 DOI: 10.1117/12.2064367

Nima Khatibzadeh, A. Stilgoe, A. A. Bui, Yesenia Rocha, G. Cruz, T. Nieminen, H. Rubinsztein-Dunlop, M. Berns

引用次数: 1

Inducing forced and auto oscillations in one-dimensional photonic crystals with light 光诱导一维光子晶体的强迫振荡和自振荡

Optics & Photonics - NanoScience + Engineering Pub Date : 2014-09-16 DOI: 10.1117/12.2064363

J. E. Lugo, R. Doti, N. Sanchez, J. Faubert

引用次数: 3

Momentum measurements with holographic optical tweezers for exploring force detection capabilities on irregular samples 动量测量与全息光学镊子探索力检测能力的不规则样品

Optics & Photonics - NanoScience + Engineering Pub Date : 2014-09-16 DOI: 10.1117/12.2061940

F. Català, F. Marsà, A. Farre, M. Montes-Usategui, E. Martín-Badosa

引用次数: 2

Nanoelectronic synaptic devices and materials for brain-inspired computational architectures 脑启发计算架构之奈米电子突触装置与材料

Optics & Photonics - NanoScience + Engineering Pub Date : 2014-09-16 DOI: 10.1117/12.2065261

R. Jha, S. Mandal

引用次数: 1