Suppressed carrier density for the patterned high mobility two-dimensional electron gas at gamma-Al2O3/SrTiO3 heterointerfaces

Abstract

The two-dimensional electron gas (2DEG) at the non-isostructural interface between spinel gamma-Al2O3 and perovskite SrTiO3 is featured by a record electron mobility among complex oxide interfaces in addition to a high carrier density up to the order of 1E15 cm-2. Herein, we report on the patterning of 2DEG at the gamma-Al2O3/SrTiO3 interface grown at 650 °C by pulsed laser deposition using a hard mask of LaMnO3. The patterned 2DEG exhibits a critical thickness of 2 unit cells of gamma-Al2O3 for the occurrence of interface conductivity, similar to the unpatterned sample. However, its maximum carrier density is found to be approximately 3E13 cm-2, much lower than that of the unpatterned sample (1E15 cm-2). Remarkably, a high electron mobility of approximately 3,600 cm2V-1s-1 was obtained at low temperatures for the patterned 2DEG at a carrier density of 7E12 cm-2, which exhibits clear Shubnikov-de Hass quantum oscillations. The patterned high-mobility 2DEG at the gamma-Al2O3/SrTiO3 interface paves the way for the design and application of spinel/perovskite interfaces for high-mobility all-oxide electronic devices.

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References in corpus (13)

• Direct imaging of the coexistence of ferromagnetism and superconductivity at the LaAlO3/SrTiO3 interface
• Metallic and insulating interfaces of amorphous SrTiO3-based oxide heterostructures
• A high-mobility two-dimensional electron gas at the heteroepitaxial spinel/perovskite complex oxide interface of γ-Al2O3/SrTiO3
• Two-dimensional quantum oscillations of the conductance at LaAlO3/SrTiO3 interfaces
• Quantization of Hall Resistance at the Metallic Interface between an Oxide Insulator and SrTiO${}_3$
• Visible light enhanced field effect at LaAlO3/SrTiO3 interface
• Room temperature formation of high-mobility two-dimensional electron gases at crystalline complex oxide interfaces
• In-plane electronic confinement in superconducting LaAlO${}_3$/SrTiO${}_3$ nanostructures
• Tunable electron-electron interactions in LaAlO3/SrTiO3 nanostructures
• Anomalous orbital structure in a spinel-perovskite interface $\gamma$-Al${}_2$O${}_3$/SrTiO${}_3$
• Quantum longitudinal and Hall transport at the LaAlO3/SrTiO3 interface at low electron densities
• Patterning of high mobility electron gases at complex oxide interfaces
• Effect of Sr-doping of LaMnO3 spacer on modulation-doped two-dimensional electron gases at oxide interfaces

Cited by in corpus (4)

• Giant tunability of the two-dimensional electron gas at the interface of gamma-Al2O3/SrTiO3
• Direct demonstration of the emergent magnetism resulting from the multivalence Mn in a LaMnO3 epitaxial thin film system
• Characteristic Lengths of Interlayer Charge-Transfer in Correlated Oxide Heterostructures
• High-quality Nano-patterning of Oxide Interfaces Using Transferred Gold Mask