The two-dimensional hole gas in TiDx/STO heterostructures

Abstract

Since the discovery of the 2DEG at LaAlO3/SrTiO3 heterointerface, oxide/oxide heterostructures have been studied extensively. However, there are only a few studies about the transport properties of metal/oxide heterostructures. In this thesis, I report that a 2DHG is found in the TiDx/STO heterostructures at temperature below 30 K. This 2DHG coexists with the 2DEG existed at room temperature. Remarkably, excessive deuterium doping in TiDx/STO heterostructure vanishes the 2DHG as well as no deuterium doping. Moreover, I also found that the 2DHG is not present in the TiDx/YSZ heterostructure. This result suggests that the 2DHG is dependent on the STO substrate and is not a novel electrical property of TiDx alone.