Tours Through Physics: Nanoplasmonics (Part 2), Sensing, Science and Diagnostics

[@AbdelRahmanAllan]

I started getting addicted to your videos, thank you so much for the clear explanation.

[@ShirinRose]

Great video! My PhD was on gold nanoparticles. I was looking at how different ligands affected their thermal stability, but my introduction/literature review chapter talked a fair bit about LSPR, and one of my experiments measured the colour changes of thin films of gold nanoparticles as they were heated and began fusing together. I did one training session on using the SERS instrument, but I never did end up using it after that.

[@DSeyit]

Please continue your work. You are really good at presenting. Thanks!

[@BritishBungler]

Thanks for creating this video. It helped me by pointing towards literature to read up on.

[@ravishanker8539]

Thanks for creating and sharing .. very useful in attaining broad understating. Eager to listen the final part (3rd one) of this series! Just wondering if there is a plan to do a video on cavity plasmonics?

[@nasrin9801]

GREAT video! bring the hard subject understandable even for those are not in the field!

[@ItsTheSebbe]

5:44 This reminds me a lot of Atomic Force Microscopy. What is actually the benefit of pointing the laser at the tip, compared to AFM where they point the laser at the top of the cantilever and look for deflections? Is it that with this method you can also obtain chemical information instead of solely topological information?

[@atomsandsporks6760]

Yes, basically. I'm not an experimentalist, but in AFM, in a typical mode of operation (there are a bajillion modes of operation), I'd say you're more or less determining a topographical surface of constant force, along a material surface. The role of the laser is simply to measure very accurately the deflection of the record needle due to things like electrostatic repulsion which is then fed into some feedback system that resets the needle-surface separation to maintain constant force. So the laser is just a deflection sensor and you're building an image of the force topography of the surface. In TERS the laser is basically driving plasmonic field enhancement around the tip, which is increasing the strength of Raman spectroscopy data by something like 10 orders of magnitude. So you're spatially resolving Raman shift, which tells you about the chemical make-up, environment and chemistry occurring under the tip. So you're not getting an image (so no pretty pictures), but rather assigning spectroscopy data to every point along the surface. The laser is necessary because without plasmonic enhancement the Raman shift signal would be too weak to detect. Though, if you told me that AFM systems and TERS systems buy their cantilevers from the same bulk-discount cantilever store I'd believe you. In fact I'd imagine there's a lot of overlap in real nitty-gritty details of building such systems (though again, caveat emptor, I have never so much as touched a Scanning Probe Microscope). I also imagine there are hybrid systems capable of combining TERS and AFM. However, the final data you get out in the two approaches is quite different (force vs. Raman spectra) but in both cases it is spatially resolved.

[@sl2357]

Fascinating! How to make jagged / rough metal surface, please?

[@marshell13]

That's a whole bunch of potential uses. Hopefully we will get some new research about the nanoplasmonics in the next few years.

[@MA-ee1pm]

Thanks for such a clear description.

[@br3nto]

Did you ever do the video on computer applications of surface plasma ice??

[@atomsandsporks6760]

Not yet I'm afraid :(

[@RainerSh19191313]

Where can the Part3 be found you mention in the Video? Really looking forward to see it as the first two parts were already really good and helpful!

[@atomsandsporks6760]

Working on it now. Could be a couple weeks though, unfortunately.

[@MarioCarpinteiroDigitalDesign]

It would be great to see that. I pressed the "Next video" button and saw 20 minutes of how to cool atoms to absolute zero temperature, and it was fantastic, but I thought, "What does this have to do with nanoparticles?". I'm a little slow hahaha

[@InquilineKea]

is this a form of surfaced-enhanced raman?

[@gretchenshen4767]

excellent video, still waiting for your third video!!!

[@atomsandsporks6760]

I''m working on it now, apologies. Didn't want to do three in a row on the same topic. Should be there in a few weeks at most (hopefully).

[@buzz5602]

Did the 3rd video get made?

[@atomsandsporks6760]

It didn't. But it will be, probably in a few weeks.

[@buzz5602]

Great! Thanks!

[@FaruqAtilola]

Thank you!

[@dulanjalirodrigo7035]

so interesting...

[@j.mohammed8073]

Where is the third part?

[@atomsandsporks6760]

Sorry, it actually will be coming relatively soon. I originally didn't do it because I didn't want to become the "nanoplasmonics guy".

[@raviinduamit]

Can you or anybody provide part three please?

[@atomsandsporks6760]

It'll be coming soon (as in in the next few weeks). I just didn't want to do three in a row on the same topic and have people get bored.

[@harleysuchiang4682]

Where's part 3?

[@atomsandsporks6760]

Coming relatively soon actually. Only took about a year ;)