Question: what made you use light in your experiments?

Susan Skelton answered on 22 Nov 2013:

Thanks for the question, mel3gill!
Light is really useful for what I do – in fact I use light because nothing else would do the job so well!

I study really really small things – the smallest things in the universe. Things like atoms, molecules, and cells. I want to be able to stick these atoms together, like tiny lego bricks, to build exciting new materials, ranging from brand new medicines to tiny robots!

But because the atoms are so small, they are really difficult to work with. They are billions of times smaller than our fingers, our even our most delicate tools, so how could we make sure that we pick up just one atom or molecule? Even if we could, how could we manage to position it so carefully so that two of our atom lego bricks could join together?

We could never make a tool that could do that…. but light can! Light can be concentrated down to a tiny area, much smaller than any tool that we could make. We can pick up atoms and molecules by holding them in this bright spot of light and put them wherever we want! I hope that eventually I will be able to build a miniature nano-robot in this way – thousands of times smaller than the width of a human hair!

Light has another advantage: because we don’t touch the things we pick up and move about, they stay completely clean. This is really important when I want to pick up biological things like cells, because otherwise they could get contaminated by bacteria or viruses on a dirty tool which could cause the cell to become ill and die.