Quantum Technologies with ultracold atoms for interferometry

Ultracold atoms are a very useful tool in Quantum Technologies for building practical measurement devices. Of particular interest are rotation sensing devices with applications in quantum-based, autonomous navigation devices. Our research programme in the experimental quantum optics and photonics group uses quantum gases, cooled to ultralow temperatures to create Bose-Einstein condensates (BECs). These Bose-Einstein condensates are a versatile tool for precision measurement. Atomic clocks are a shining example of the power that technology based on atomic physics can have. In the last decades, using atoms laser cooled to the microkelvin regime, the sensitivity of atomic clocks is now better than one second over the age of the universe.
One of the key aims of our research is the demonstration of a device using integrated optics for BEC interferometry. A possible outcome would be the translation of BEC technology into a practical navigation tool. This project will build on our existing activities at Strathclyde in atom interferometry with coherent matter waves and work on ring-shaped guided traps to explore the possibilities for developing miniaturised technology for rotation sensing. We will use microfabrication technology (published in Nature Nanotechnology, May 2013: dx.doi.org/10.1038/nnano.2013.47), which we have developed for miniaturisation of laser cooling setups with the prospect for arbitrary design of optical potentials.
Magnetic ring traps are also a versatile tool to trap ultracold atoms as a coherent matter wave confined in a ring trap is formally equivalent to the coherent optical field (laser) in a ring cavity known from the ring laser gyro. The interesting difference, though, is that the sensitivity to phase rotation scales with the relativistic energy of the particle/wave involved. For atoms that is about eleven orders of magnitude larger than light. For a practical realisation this is not all achievable as the enclosed area will be smaller as will be the number of particles detected. However, a significantly increased sensitivity seems achievable. If we estimate the signal (interferometer phase shift) obtained from the Earth rotation we find that 1 km of fibre wound on a 10 cm diameter gives a shift of 0.1 mrad, whereas a realisable 3 mm diameter atom interferometer will see a shift of more than 1 rad.
These devices seeks to integrate several challenging technologies, which we are currently developing in the research labs. It is envisaged that the project will inform the potential future development of an industrial proto-type benefitting from the experience gained in e.g. the miniaturised atomic clock project proposed to run in parallel.
There are two main strands to the present project. The student will participate in the existing research programmes in BEC interferometry at the EQOP group and in parallel with that apply existing knowledge in the development of a micro-fabricated device. A key aim is the demonstration of an integrated device for laser cooling and BEC interferometry, which can also be used for quantum simulation, if optical lattices structures were integrated. This project would ultimately inform the translation of chip-based BEC technology into a practical tool.