Particle-wave-duality is one of the cornerstones of quantum physics. Assigning wave properties to rest-mass particles such as atoms enables the construction of matter wave optics, in particular atom interferometers and gyroscopes.

There is however a fundamental difference between photon and atom optics: While photons do not interact, atom-atom interactions lead to an intrinsic non-linearity in the matter wave dynamics. As these interactions can in principle be controlled (concerning both, sign and magnitude), this adds a powerful degree of freedom to explore new physics regimes, fundamentally inaccessible to photon optics.

The tunability of atom interactions is however not yet fully exploited in matter wave optics. The aim of the iWave project is to establish matter wave optics with tunable atom interactions to realize a new class of experiments that go beyond the photon analogy. In particular, we aim to fully exploit the many-particle coherence, correlations, and entanglement of Bose-Einstein condensates in interferometry experiments for fundamental investigations and metrology applications at the quantum limit.