Quantum-Degenerate Gases for Precision Measurements (QuDeGPM)

Atom interference has been applied in many pioneering experiments ranging from fundamental studies to precision measurements. The techniques of laser cooling and trapping have allowed the realization of bright sources of macroscopic matter waves. This project is part of a EUROCORES Collaborative Research Project (within the EuroQUASAR programme coordinated by ESF) whose goal is to build upon this expertise and use interference of quantum degenerate macroscopic matter waves for a new generation of precision measurements. Two sets of applications are envisioned: (1) Precision determination of fundamental constants and inertial forces in free space, and (2) Interferometers for trapped atoms close to the surface as a microscope for highly sensitive measurements of surface forces on the micron length scale. To achieve the ultimate sensitivity we will engineer the interactions between the atoms and create non-classical matter-wave quantum states to beat the standard quantum measurement limit. Ultracold degenerate quantum gases with their inherent coherence and narrow spread in space and momentum promise to be the ideal starting point for precision matter wave interference experiments, similar to lasers for light optics. In contrast to light, atoms interact with each other, and the physics of degenerate quantum gases is in many cases dominated by these interactions. This can be an advantage, allowing tricks from non-linear optics like squeezing to boost sensitivity, and a disadvantage, resulting in additional dephasing due to uncontrolled collisional phase shifts. We will exploit recent advances in controlling these interactions by Feshbach resonances to pick out the advantages and to suppress the disadvantages caused by the interactions. Much of the planned work will be very fundamental and exploratory as many of the capabilities together with possible limitations have yet to be investigated.The collaborative research project entitled Quantum-Degenerate Gases for Precision Measurement (QuDeGPM) focuses European efforts on precision measurements with quantum degenerate gases and in particular with Bose-Einstein condensates (BEC). The project is organized along the main objectives of (i) performing precision atom interferometry with quantum degenerate gases, (ii) using quantum degenerate gases for precision surface probing, and (iii) exploring, realizing, and testing novel measurement schemes with non-classical matter wave states. The project in Durham focuses on the use of matter-waves with tunable interactions to probe atom surface interactions. Specifically two experimental thrusts are planned. The first uses bright matter-wave solitons as the basis for a new form of matter-wave interferometry. This work connects to an existing project which began in January 2008 (EPRSC grant EP/F002068/1). The second thrust exploits condensates where the interactions are tuned to zero to study long-lived Bloch oscillations in a 1D lattice in the vicinity of a solid surface.