Week+of+Sep+21-25

=Week of Sep 21-25 =

23rd of September
I went to the lab for 2 hours and 30 minutes. I was able to get 11 actual images and performed many scans where I shot the laser at the sample. After I shot the sample the first time with the laser I opened the box the scope is in to align the laser better. I do this because when we first align the laser we block the hole in the back of the sample holder so we can see about where it will hit. We do not want to hit the sample before we scan so that we see a before and after image. Once We have before images and the sample has already been shot I can then align the laser shooting it at the sample. I alligned the laser and then closed the box and restarted scanning. When I performed a single line scan and shot the sample with the laser I got a 6000 angstrom expansion of the gold. This is the larges expansion thus far, however this is the entire range that the tip can move while it is scanning on the current settings. The tip can only move 6000 angstroms away from the sample. 6000 angstroms is a low bound because it actually crashed and by the section view it still appeared to be increasting when it crashed. I did this several times and everytime the feedback needle went all of the way across. The tip crashing, while it sometimes improves the tip did not do so this time. The tip became worse after it crashed and it didn't provide very good after images of the surface.

25th of September
I went to the lab for 3 hours. Today in the lab I mostly tried to get before and after images of the gold sample. This sounds much easier than it is. I would take a scan, then I would shoot the laser at the sample while doing another scan, and then I would scan again afterwards. However, the area was not the same area as before because the scope was drifty, but not as drifty as it has been lately. I did get a couple scans of the same area both before and after I shot the laser, but they did not appear to have changed. Over the 3 hour period I got 22 scans. I tried shooting the sample while not scanning to see if this would make it easier to scan the same area before and afterwards because I thought you wouldn't have to worry about the tip moving. But I still did have the same areas before and after. So basically I took a bunch of scans before of different areas, then I shot it with the laser and then took a bunch of scans afterwards to see if I could find an area I had scanned earlier. I was still getting 6000 angstroms of expansion and I tried changing around many different things such as the gain, scan size, or the line time.

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