Cooling and optical systems of a nanodiamond in a magneto-gravitational trap towards the generation and detection of a spatial superposition state

Single nitrogen (NV-) centres in diamond have isolated electronic and nuclear spins that can store quantum information at room temperature for over one second. Using a magneto-gravitational trap to levitate nanodiamonds it is theoretically suggested that, once cooled, the nanodiamonds could be placed into a superposition of spatial states. The long-term goal is that this method will test the limits of macroscopicity for a spatial superposition state.
The PhD project begins with building the magneto-gravitational trap so that consistent trapping is achieved at room temperature and pressure. The next step is implementing the vacuum and helium gas cooling systems that will take the chamber containing the trap to high vacuum and to 8K respectively. Along with the vacuum and cooling systems the PhD project will also include designing and building the required optical and electronic setups to carry out the desired measurements on the trapped nanodiamond. These include excitation and detection setups for the NV- centre photoluminescence. The PhD project will then move towards the detection and verification of the presence of a spatial superposition state, with the aim of generating as large a superposition as possible. This could be done whilst the diamond is trapped or in free fall.
Alongside the work on the levitated experiment, the PhD project will include work on other non-levitated setups. For example, an existing room temperature confocal microscope will be used in order to characterise nanodiamond samples, before trapping them in the levitated experiment.