Master thesis defense by Dennis Christensen

Exploring the interfacial conductivity and resistance switching in amorphous LaAlO3/SrTiO3 heterostructures


Oxide materials have attracted a lot of interest as this class of materials exhibits a plethora of remarkable properties. In particular, at the interface between the two insulating oxides LaAlO3 and SrTiO3, a 2-dimensional electron gas (2DEG) is formed, which displays superconductivity, resistance switching, magnetic ordering and the ability to draw and erase circuits on the nanoscale at room temperature. Despite intense research, the origin of the 2DEG remains unknown. In this thesis a new approach towards understanding the origin of the 2DEG is presented in which amorphous LaAlO3 (a-LaAlO3) is deposited on SrTiO3. Using this approach, the origin of the 2DEG is explained. Armed with the knowledge of the origin, routes for enhancing the carrier mobility, preventing degradation of the interfacial conductivity and spatially patterning the 2DEG are found.

The discovery of a bipolar resistance switching in the a-LaAlO3/SrTiO3 is furthermore presented. Using the electric field from a back-gate, a non-volatile change in the resistance exceeding 3 orders of magnitude is observed.

Master thesis defense by Dennis Christensen


Note that a presentation of the same thesis will be given by Felix Trier in D317, HCØ, 13.15-15pm, 2nd of March. Felix' presentation will be followed by a reception in D203, HCØ, for both Felix Trier and Dennis Christensen.