Exploring the possibility of making a low barrier to entry nano-imaging system

A brief history

This build is inspired by many trailblazers before myself, and I will link to as many of them as I can. One YouTube channel that is invaluable for the citizen scientist is Applied Science by Ben Krasnow. Check out his channel here:

https://www.youtube.com/@AppliedScience

It seems like every kid interested in science asks some like this:

“What are things made of?” says the kid, the parent/teacher says “Molecules”. The curious child then says “What are molecules made of?”  then “Atoms” becomes the reply, then perhaps protons and neutrons, then quarks. but eventually the answer is “We don’t really know”. If you are like me then that sense of wonder doesn’t die out. While I won’t be seeing quarks, I’m excited to try to build a machine that can detect individual atoms.

Inspired by posts like this

Home-Built STM

and old research papers like this:

https://web.archive.org/web/20030508182417/http://www.nanoworld.org/museum/young2.pdf

I decided to set out trying to make a wide field version of the same thing. I am thinking that I should be able to add stepper motors to a micrometer stage and use that as my coarse adjustment for the STM tip. I wanted to characterise the movement of the piezo disks and the stage, so I built the self-mixing interferometer described here:

And was able to get the following results:

This is the piezo being fed a sign wave at 1khz with a 2v P-P voltage

and this is the same setup with 1khz but at 4v P-P

I still need to get the electronics set up better and the retro-reflective tape is on it’s way, but I was really happy to be able to measure 300nm-ish movements.

The next step I hope to tackle is designing the mounts for the stepper motors to the micrometer xyz stage.