Physicist

"The problem is this: You have an S-shaped lawn sprinkler – an S-shaped pipe on a pivot – and the water squirts out at right angles to the axis and makes it spin in a certain direction. Everybody knows which way it goes around; it backs away from the outgoing water. Now the question is this: If you had a lake, or swimming pool – a big supply of water – and you put the sprinkler completely under water, and sucked the water in, instead of squirting it out, which way would it turn? Would it turn the same way as it does when you squirt water out into the air, or would it turn the other way?" Feynman, R. Surely You're Joking, Mr Feynman! (1985). 

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Trying to answer this question was my first experience of doing physics. I spent the summer of 2010 trying to do this experiment with a friend - we went to hardware shops to get piping, we got soaked trying to attach a hosepipe to our tube, and we never quite convinced ourselves of the answer. It was challenging, fun and sociable. During my undergraduate degree, I spent summers in different labs, trying to find an area of research that clicked with me and gave me the same joy as the s-shaped tube. I tried particle physics at CERN (too much time on a computer), magnetism at the Bangladesh Atomic Energy Commission (magnetism is confusing) and quantum optics at the University of Toronto (shame to spend the summer in a dark lab). Finally, I found a home in a condensed matter lab at the University of Cambridge. 

 

My MPhil and PhD theses were both on electron transport in nanodevices. I love this area because it combines precise work on tiny devices, operating big machinery to reach very cold temperatures and a lot of very interesting physics. For my MPhil, I looked at 1D systems - a long chain of electrons in a wire - and how these behaved as the wires got smaller and smaller. For my PhD, I investigated topological insulators - an odd material that is somewhere in between a metal and an insulator. Here is a video of me explaining the topic in Bengali (with English subtitles):