Optical Trapping Of PolyBalls

Above is a very basic outline of the apparatus I will eventually be working with towards the end of term. My experiment will attempt to optically trap a suspension of polystyrene beads using a evanescent field produced by propagation of 1480nm light through a fibre. In a previous experiment credited to Brambilla, Murugan, Wilkinson, Richardson, some of the beads were trapped not only by the field, but also through resonance with the field in the form of a whispering gallery mode. The set-up is essentially entirely foreign to me which makes it doubly exciting - getting to grips with each component (mostly through extensive googling of their model numbers).

Sile ordered me a photodetector which I had a look at today. I have a diode laser and I'm waiting for Kieran and Michael to finish with the current and temperature drivers. I'm also waiting on an SMA adaptor because of the non-standard fitments on the detector... I was very boggled trying to locate this adaptor - blissfully unaware of the sheer amount of adaptors and cables and fittings!

While I wait for the temperature and current drivers to become available, I'm going to try and use the detector with another laser. Then, my first task is to characterise the laser as a function of driving current.