查看完整版本: 一种基于干涉原理的纳米结构三维成像方法

一种基于干涉原理的纳米结构三维成像方法

[size=5][b][color=Blue]Nanostructures Imaged in 3-D [/color][/b][/size]
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U q@\K(RM*i!M 【纳米科技世界论坛快讯】[b]An optical technique more than acentury old has helped solve a major problem with surface electron microscopy -- the inability to receive depth information about a sample-- and now allows fast-moving nanostructures to be imaged in three dimensions and in real time.  [/b][/color]9Jtg0\0p5UOv
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Monash University physicists David Jesson, Konstantin Pavlov and Michael Morgan solved the problemby developing a new technique that incorporates an experiment from the1800s to determine surface shape and depth. The breakthrough willenable scientists to see, in real time, fast-moving images of thetiniest droplet or the smallest structure evolving and be able to seehow they behave and interact on surfaces.[/b]
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#sk.U:MK$wM 澳大利亚莫纳什大学物理学家最近利用18 世纪就已经存在的一个光学实验方法实现了纳米结构的三维快速实时成像，以帮助科学家弄明白在物体表面微小的纳米结构体是如何形成以及相互作用的。研究者利用劳埃德镜（18 世纪的著三维成像原理图名光学试验，利用分光镜将光束分成两束，直射光和反射光形成相干光，在屏幕相遇区产生干涉条纹）原理，采用紫外光照射材料表面，通过形成的干涉图像（干涉图像不但记录了平面图像信息，而且记录了相位信息，即平面上凹凸状况信息），实现了对纳米结构体的三维成像。kxO H4nT6G-M+J`
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Source：Monash University

Nanostructures Imaged in 3-D

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\ Schematic showing how a 3-D line profile (white line) can be obtained from Lloyd's fringes in surface electron microscopy.[/color][/size][/font][/align][align=center][font=Arial][size=2][color=#808080] (Image courtesy MonashUniversity)[/color][/size][/font]
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[/align]"How materials develop and react with other materials forms the basis of a great deal of scientific research, and what we have achieved is the ability to view small clusters on surfaces as they are evolve and interact," professor Jesson said. "Previously,scientists have had to freeze-frame each image by removing specimens from the growth or heating environment and link them together. Our discovery means that images can be now captured as a real-time video which also shows the depth of the structure. This will open up new opportunities for theorists to model and understand the changes in nanostructures being developed for a new generation of computers,lasers and communication systems, and is a new tool for studying surface shape dynamics on small-length scales." a-e!l*O&PVY Hy
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Jesson's team discovered 3-D imaging of nanostructures is possible while using photoemission electron microscopy, or PEEM, to look at droplets of liquid gallium sitting on a mirror-flat surface of gallium arsenide. E9_!]*k#|V
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I+HnB "We created interference fringes by illuminating the droplets with ultraviolet light using a classic 19th century physics experiment known as Lloyd's Mirror, where light reflected off a mirror interferes withlight coming directly from the source," he said.
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J-EZ3Og They found that the bright interference fringes result in the emission of electrons which can be imaged using a surface electron microscope.Applying the same principle as viewing a standard topographic map of amountain range, they were able to determine the height of the structure by counting the contour lines.
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"Fringes are sensitive to the 3-D shape of the gallium droplets and are distorted by the electric field due to the topographic features. This can then be corrected using image processing, to provide a real-time relief map showing how the surface of the metallic droplets evolves," Jesson said.
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This work was recently published in [i][b][/b][color=Purple][b]Physical Review Letters[/b] [/color]99[/i] and is also featured in the [color=DarkRed][i][b]Physical Review Focus[/b][/i] [/color]of the American Physical Society. 1wZ `(H5\WF
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More information, visit: [url=http://www.monash.edu.au/news]www.monash.edu.au/news[/url]