wow, i can't believe it-**yay**! so so happy and thankful to all that voted for me and kept me here till the end, it's been a brilliant fortnight, spreading the joy of science, i've loved it! more answers to questions still to come if i can
Meole Brace Secondary School 1998-2003, Shrewsbury Sixth Form College, 2003-2005
Physics at University of Oxford, 2005-2008, Physics PhD at University of Strathclyde 2008-present
experimental research PhD student
Central Laser Facility, Rutherford Appleton Laboratory
I’m a laser plasma physicist, which basically involves shooting ridiculously intense laser pulses at tiny targets and looking at all the stuff that comes flying off with a view to use this interaction, for example, to build a compact particle accelerator.
Check me out in this 5 min film for a sneak peak of where i work and then read on if you want to know more (sorry it’s a bit long):
I’m in the very fortunate position to be working and studying from within the Central Laser Facility at Rutherford Appleton Laboratory in Oxfordshire. Here we have two of the most powerful lasers in the world. The lasers that we use for our experiments are incredibly intense packets of light, so intense that we only need one single laser pulse at a time to carry out all of the exciting physics that we want to study. A nice comparison is to imagine taking all of the sunlight shining on our earth’s surface and send it through a humongous lens that focusses the light down to a tiny spot the size of a pin………all of that light squeezed into a few mm……..well that’s the same intensity of light that we can achieve with our lasers……..although the laser pulses only last a trillionth of a second (that’s a picosecond for those in the know) so no worries, we’ve got it all under control.
So what can we do with these insanely powerful toys?
Well, we use a single laser pulse to create a plasma. A plasma is like the fourth state of matter. It’s when a material is under such extreme conditions (temperature and super strong electric fields in the case of a laser interaction) that the electrons are stripped from the atoms. What you then have is a charged gas, by which I mean you’re in a state whereby electrons and positively charged atoms (ions) are all swimming round together in a gaseous cloud. The kind of plasmas that we can create in the lab using an ultra intense laser pulse are as hot as the centre of the sun and under these conditions, lots of exotic physics takes place.
Physicists want to create plasmas so that they can study it and understand it better. Believe it or not, plasma is the most common state of matter in the universe. You’ll find it everywhere in space: between planets, between galaxies and our sun (and all other stars for that matter) is a great example of a super-sized ball of plasma. Here on earth, lightning is a result of plasma formation, so too are the beautful northern lights in the polar aurora. And then there’s plasma tvs, strip lighting, neon signs, plasma balls……….OK you get me, it’s pretty much everywhere and most people haven’t even heard of it.
So what can we do with a laser plasma interaction?
One really exciting application is the ability to achieve fusion using lots of powerful lasers, all shining on a tiny (a few millimetres) pellet of dueterium (D) and tritium (T) fuel. If we can make these two elements (D+T) fuse together, then loads of heat energy is released. If we can control and keep this fusion reaction going constantly, then we can use this an energy source for a power station and replace the burning of fossil fuels or nuclear reactors with the fusion process. It doesn’t produce any harmful gases, there’s no chance of a runaway chain reaction and the fuels that we need (D + T), well there’s enough of it here on earth to last us millions of years. Could this be anymore perfect to solve our energy crisis and the fact that if we don’t sort this out, then our grandchildren will have to ration their electricity? can you imagine it? life without electricity? how many things would we not be able to do? It blows my mind. Anyway, never fear, for plasma physicists are here, to literally save our world with some clever laser plasma interactions.
And finally, how to build a table-top particle accelerator. When we shoot an ultra intense laser pulse at a small piece of material (we call it a target) like gold, plastic or aluminium, it’s instantaeously plasmified (is that word? it definitely should be, ha) then what we find is that a high energy particle beam comes flying off the back surface of our target. We can accelerate particles over a tiny distance (something like a millionth of a metre), whereas conventional accelerators that use big and heavy magnets (like CERN for example) need metres to achieve the same particle energy! This means that using a laser-plasma accelerator, we have the potential to build compact and flexible particle beam sources that don’t require huge buildings and thick, expensive walls for radiation shielding. This will be useful to medical people, researchers and people in industry that want to have their own particle beam source withough having to buy a huge, chunky convential machine. However, we’ve got our work cut out before we can safely say that we’ve got a tunable and well-controlled particle beam using a laser pulse. And that’s what I’m working on. I carry out experiments to see how changes in the laser pulse properties (it’s energy in joules, spot size in micrometers, duration in picoseconds) effect the type of particle beam that we end up with (what the maximum energy is, how many particles we accelerated, how wide the beam is etc). It’s a really cool area of experimental physics, if only for that fact that we actually have a ‘fire’ button in the control room!
Here’s some pictures of me in the lab:
in the first one you can see a piece of real data taken during an experimental campaign. It’s a piece of film that has had a proton beam pass through it. as the proton beam passes through, it turns the chemical in the film blue and so we can see a footprint of where the proton beam has been. we can use this to measure how many protons were accelerated in our laser plasma interaction and how high the energies are.
here’s a picture of me in the target chamber, placing a target (the tiny gold thing in the middle of my face mask) at the centre of the chamber ready for a laser shot. We have to wear all the overalls, hood and gloves so that we keep the chamber as dust free as possible!
My Typical Day:
I’m at the end of my PhD so I’m writing my thesis at the moment which means my days consist of writing up my experiments, plotting graphs, trying to figure out the physics of why we see what we do in the results by reading other research papers and then discussing all of this with my supervisor.
What I'd do with the prize money:
I’d use it to help me promote the joys of laser plasma science
I’ve got a few ideas so far:
i’d like to produce small cards about laser plasma science that are quick and easy to read and then leave them in bars, cafes, common rooms etc so that everyone can pick them up and grab a plasma fact (i think the IOP have done something similar before for physics, so maybe they can give me a hand 🙂 ) maybe i can even send them out to schools……..
i’d also like to be able to produce super cool talks, presentations and short films about laser plasma science that i can wow people with and then take them into schools and public venues. i need to pay for some really nice animations though as I can’t do a good enough job myself
*ideas still brewing*
How would you describe yourself in 3 words?
smiley, thoughtful, determined
Were you ever in trouble at school?
Who is your favourite singer or band?
(This list will grow for sure) Adele, Beyonce, Kings of Leon, Hadouken, Florence and the machine, Example, Mumford&Sons,
If you had 3 wishes for yourself what would they be? - be honest!
1) The basics: wealth, health, love and happiness forever 2) To stop biting my nails (soooo bad) 3) That my thesis would write itself
Tell us a joke.
Have you heard about the expert scarecrow? I hear he’s outstanding in his field! baaaahahahahaha