Research Projects

In the last two decades, SrTiO₃ (STO)-based two-dimensional electron gases (2DEGs) have exhibited a variety of remarkable phenomena including Rashba spin-orbit coupling, gate voltage tunability, superconductivity and the quantum hall effect. These properties position oxide-based 2DEGs as one of the prime candidates for spintronics applications, particularly for enabling spin-charge interconversion essential for advanced logic-in-memory devices. Intel proposed magneto-electric spin-orbit (MESO) device highlights the relevance of such systems, due to their potential to surpass conventional CMOS technology by leveraging spintronics for energy-efficient computing. The bottleneck for practical applications of these 2DEGs lies in their integration with silicon (Si) technology. Freestanding oxide-based 2DEGs offer the flexibility to be transferred onto Si substrates, facilitating their integration into existing technological infrastructures. This project aims to explore the exciting physical properties of freestanding STO-based 2DEGs and their potential for future spintronics applications, especially in post-CMOS technology. The recent development in the fabrication of millimeter-scale epitaxial single-crystal oxide membranes using water-soluble sacrificial layers method has enabled the possibility to integrate these membranes onto other substrates while retaining their crystal structure and properties. However, the transport and electronic properties of these freestanding membranes, such as charge carrier density, mobility, and spin-charge conversion, remain largely unexplored. This proposal focuses on fabricating freestanding STO-based 2DEGs using sacrificial layers like Sr₃Al₂O₆ (SAO) or La₀.₇Sr₀.₃MnO₃ (LSMO) and transferring them onto Si substrates. Once the freestanding layers are fabricated, their transport properties will be thoroughly investigated, including multiband transport, gate voltage tunability, and spin-to-charge interconversion. Moreover, the Rashba spin-orbit interaction, which allows spin-charge interconversion, will be analyzed using bilinear magnetoresistance (BMR) techniques to extract the Rashba coefficient. The overall goal is to understand and optimize the properties of freestanding STO 2DEGs, contributing to the development of spintronic devices for future computing architectures.