Profile

Hello! My name is Dave and I’m a Physics PhD student at the University of Nottingham.

My work can be summarised very simply as hitting things with a stick and watching them wobble, except that the things are 1000 times thinner than a human hair, and the stick is actually a laser.

Specifically, I vibrate very, very thin layers (about 100 billionths of a metre) of polymer molecules. To vibrate them, I attach them to a similarly thin metal layer, and then hit that with a very short pulse from a very powerful laser. This causes the metal to heat up and expand very suddenly, which wobbles the polymer layer. I can look at exactly how the polymer wobbles by bouncing another laser beam off it and measuring how the power of that beam changes. By doing this I can learn things about the structure of my polymer samples and what properties they have.

I also like to spend my time showing people outside of the University how fun and interesting Physics is (it is, honest!). I normally try do this with lots of demonstrations and, if possible, liquid nitrogen whenever I can find an excuse. For example, here is the finale of a live show I did recently where a make a cloud using some liquid nitrogen… 25 litres of it in fact!

When I get in I’ll go to my desk, have a coffee and sort out some emails. As you can see, my desk is kept in a Zen-like state of order:

At this point I’ll start to hide from my supervisor so he can’t give me anything else to do on top of what I already have. This never works so I’m soon off down to the lab to try out his latest idea:

In my research, I’m  often trying to make new types of sample. To do this, I have to try many different things until I get what I want. This is the problem with trying to do something no-one has done before, it can be a pain, but it also feels really good when you find the right recipe to make something work. I use lots of different materials, but most often my samples are made of polymers, such as polystyrene. I also use gold occasionally, although for my work it needs to very pure, 99.999% in fact!

Once I’ve made my samples, I have to measure them, and for this I need the big laser…

Aligning this laser takes a long time, and I have to use a night vision scope to do it. This is because the laser is in the infra-red part of the electromagnetic spectrum, so can’t be seen by the naked eye.

I also have to do other things, such as writing papers for publication, but I’m primarily an experimental physicist, so I do spend most of my time in the lab. I’ve had the opportunity for travel abroad as well. Most recently I went to Switzerland to lead a team of students at the International Physics Tournament.

I love my work, and even though it can be hard when things aren’t working, there’s nothing I’d rather be doing.