Ferroelectric materials such as Barium Titanate exhibit a spontaneous electrical polarisation, which can be used in high-density, non-volatile, energy-efficient data storage devices. This research line targets the mapping of the ferroelectric polarisation in ferroelectric tunnel junctions which consist of an ultrathin ferroelectric layer epitaxially grown between 2 contacts. In fact, this work is supposed to shed light on the degradation an dysfunction of ferroelectric devices that exhibit, however, favorable geometries from the application point of view.