From low-field Sondheimer oscillations to high-field very large and linear magnetoresistance in a SrTiO${}_3$-based two-dimensional electron gas

Abstract

Quantum materials harbor a cornucopia of exotic transport phenomena challenging our understanding of condensed matter. Among these, a giant, non-saturating linearmagnetoresistance (MR) has been reported in various systems, from Weyl semi-metals to topological insulators. Its origin is often ascribed to unusual band structure effects but it may also be caused by extrinsic sample disorder. Here, we report a very large linear MR in a SrTiO${}_3$ two-dimensional electron gas and, by combining transport measurements with electron spectro-microscopy, show that it is caused by nanoscale inhomogeneities that are self-organized during sample growth. Our data also reveal semi-classical Sondheimer oscillations arising from interferences between helicoidal electron trajectories, from which we determine the 2DEG thickness. Our results bring insight into the origin of linear MR in quantum materials, expand the range of functionalities of oxide 2DEGs and suggest exciting routes to explore the interaction of linear MR with features like Rashba spin-orbit coupling.

References in corpus (8)

• Linear magnetoresistance caused by mobility fluctuations in the n-doped Cd3As2
• Non-saturating magnetoresistance of inhomogeneous conductors: comparison of experiment and simulation
• Rashba induced magnetoconductance oscillations in the LaAlO3-SrTiO3 heterostructure
• Determining the Rashba parameter from the bilinear magnetoresistance response in a two-dimensional electron gas
• Large modulation of the Shubnikov-de Haas oscillations by the Rashba interaction at the LaAlO${}_3$/SrTiO${}_3$ interface
• Tuning up or down the critical thickness in LaAlO3/SrTiO3 through in situ deposition of metal overlayers
• Metal/SrTiO${}_3$ two-dimensional electron gases for spin-to-charge conversion
• Quantum interference effects of out-of-plane confinement on two-dimensional electron systems in oxides

Cited by in corpus (2)

• Impurity and dispersion effects on the linear magnetoresistance in the quantum limit
• Linear colossal magnetoresistance driven by magnetic textures in LaTiO3 thin films on SrTiO3