Engineering Of Electron Confinement Through Defect-Based Localized Polarization On Srtio3 Surface

Electron behaviors are expected to differ in circumstances with polarization. Changes in electron dynamics further result in changes in the physical properties, especially at reduced dimensions. In this paper, threshold photoemission is used to image a 2D electron gas induced on a SrTiO3 surface with regions polarized by defect-based localized dipolar moments. It is found that the induction of surface polarization results in decrease of the surface itinerant electron density and the magnetic moments at room temperature. Such effects are attributed to the polarization-based trapping of the surface itinerant electrons. It is also demonstrated that those changes induced by surface polarization can be manipulated by varying temperature. These findings address the importance of polarization in low-dimensional electron dynamics, which offers an alternative way to engineer the properties of the SrTiO3-based 2D electron gas.