Two-dimensional (2D) materials, due to its singular properties mainly flexibility and transparency, have gathered the attention for their potential use in photonic and optoelectronic devices. Initially these studies were restricted to graphene however, its lack of electronic band gap inspired the search of semiconducting counterparts such as MoS2, Bi2Te3, h-BN etc. However, the absence of electronic correlations -i.e. the fact that electrons do not feel each other- restricts their functionalities and applications. Endowing 2D materials with electronic correlations could produce exciting groundstates such as ferroelectricity, ferromagnetism or superconductivity, which could expand their functional capabilities. In complex correlated oxides (CCOs) the unscreened Coulomb repulsion between electrons in 3d bands gives rise to a non-trivial entanglement between charge, spin, orbital and lattice, which is responsible of a wide variety of electronic groundstates. In this project we have searched for new synthesis of 2D CCOs in the strain free -freestanding- form. The general perovskite structure of these compounds requires the use of single crystalline substrates for their growth, followed by a post growth-release. This last step is nowadays a challenge and different methodologies are being considered. The most common is the use of sacrificial buffer layers which are solved under the immersion in water or an acid. However, etching procedures differ for the different materials, and depend also on the growth technique. In this regard, a careful investigation for the release of 2D CCOs must be conducted. The main objective of this project has been the manipulation of correlated states in 2D CCOs layers, and their combination with van der Waals (vdW) layers in heterostructures, in order to achieve tunable responses and device functionalities. We expected that collective states such as ferromagnetism or superconductivity will be modified when the CCOs layers are in the freestanding form when released from its substrate. On the other hand, the assembly of CCOs in vdW heterostructures is expected to yield exciting electronic states possibly with topological properties such as topological superconductivity or magnetic skyrmions. In addition, the possibility to transfer CCOs on top of Si substrates opens a huge number of opportunities to implement the unique functional properties of these materials in the devices of the CMOS technology, expanding the perspectives and functionalities of current electronic devices. This project can be framed in the field of Quantum Materials and Technologies, a global research direction which is expected to develop the so called “second quantum revolution” with exciting scientific and technological outcomes.
