Comandante Posted May 3, 2008 Posted May 3, 2008 You've probably heard of x-ray crystallography as it is a very common and useful technique used to analyse bond distances, angles etc - in simple terms - probe the atomic arrangement in crystals. Last year we had to learn in-depth how this method works and the apparatus behind it so I got that down pretty well. If you're already wondering - NO I don't know how to make one at home However, something occured to me recently. If you think about it, those green lasers have a bit smaller wavelength than the red ones, at around 532nm, and they are also better-visible to the human eye, not to mention that a decently-powered green laser can be purchased for around $80 these days. That said, you'll know why I wanted to probe a nano-engineered surface with my green laser It worked as I expected, resolution was a bit poor (due to difference in wavelength size and nano-work scale) but useful nevertheless! I took a recent genuine Intel CPU box and scanned it around for nanosignatures, wasn't long before I found one I posted a video online so you can have a look here: http://www.metacafe.com/watch/1287916/using_green_laser_to_reveal_invisible_objects/ If anyone tries this method on other nanotech objects could you please be kind to let us know what you found, would like to see more examples
John Cuthber Posted May 3, 2008 Posted May 3, 2008 Very neat, but that image is produced by microscale, rather than nanoscale, printing/
Comandante Posted May 4, 2008 Author Posted May 4, 2008 Really? How can you know? I assumed it'd be nanosig because I get better resolution with smaller wavelengths.. explain for me? Perhaps I should look this sticker under a microscope
thedarkshade Posted May 4, 2008 Posted May 4, 2008 That seemed pretty good and pretty simple. Great work Sysco.
John Cuthber Posted May 4, 2008 Posted May 4, 2008 About the simplest nanoscale object you could get would be a grating with a spacing of about 100nm ie 0.1micron. Try putting that into this calculator with sensible values for the distance to the screen and the wavelength. http://www.ee.byu.edu/cleanroom/diffraction.phtml On the other hand, you might be able to see something of the structure with a microscope.
Klaynos Posted May 4, 2008 Posted May 4, 2008 You can "see" some details of subwavelength periodic structures through things like surface plasmon polaritons, this is how most metamaterials work...
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