Creating nano-scale “vias” in LaAlO₃/SrTiO₃ for integration of nanostructures

The 2D electron gas (2DEG) at the LaAlO₃/SrTiO₃ interface exhibits a wide range of gate-tunable properties like superconductivity, magnetism, and spin orbit coupling [1]. Furthermore, the interface can be patterned with nanoscale dimensions using c-AFM lithography [2] and integrated with other 2D materials such as graphene [3]. While the surface of LaAlO₃/SrTiO₃ is only 1.2 nm from the interface, improved coupling of particles on the surface with the interface requires closer proximity. Here, we discuss methods to create nanoscale holes or “nano vias” in LaAlO₃/SrTiO₃ with the goal of integrating nanomaterials directly to interface while maintaining interfacial conductivity. These nano vias will allow us to study the effect of local coupling between the 2DEG at LaAlO₃/SrTiO₃ interface and a wide variety of interesting nanomaterials such as colloidal quantum dots or graphene nanoribbons.
[1] Yun-Yi P., et al., Rep. Prog. Phys. 81, 036503 (2018)
[2] C. Cen, et al., Nature Materials 7, 298 (2008).
[3] Huang, M. et al., APL Mat. 3, 062502 (2015).