The quasi-two-dimensional electron gas found at the LaAlO3/SrTiO3 interface offers exciting new functionalities, such as tunable superconductivity, and has been proposed as a new nanoelectronics fabrication platform. Here we lay out a new example of an electronic property arising from the interfacial breaking of inversion symmetry, namely, a large Rashba spin-orbit interaction, whose magnitude can be modulated by the application of an external electric field. By means of magnetotransport experiments we explore the evolution of the spin-orbit coupling across the phase diagram of the system. We uncover a steep rise in Rashba interaction occurring around the doping level where a quantum critical point separates the insulating and superconducting ground states of the system.

The development of new solvents is imperative in lithium metal batteries due to the incompatibility of conventional carbonate and narrow electrochemical windows of ether-based electrolytes. Whereas the fluorinated ethers showed improved electrochemical stabilities, they can hardly solvate lithium ions. Thus, the challenge in electrolyte chemistry is to combine the high voltage stability of fluorinated ethers with high lithium ion solvation ability of ethers in a single molecule. Herein, we report a new solvent, 2,2-dimethoxy-4-(trifluoromethyl)-1,3-dioxolane (DTDL), combining a cyclic fluorinated ether with a linear ether segment to simultaneously achieve high voltage stability and tune lithium ion solvation ability and structure. High oxidation stability up to 5.5 V, large lithium ion transference number of 0.75 and stable Coulombic efficiency of 99.2% after 500 cycles proved the potential of DTDL in high-voltage lithium metal batteries. Furthermore, 20 μm thick lithium paired LiNi_0.8Co_0.1Mn_0.1O₂ full cell incorporating 2 M LiFSI-DTDL electrolyte retained 84% of the original capacity after 200 cycles at 0.5 C.

The Materials Science beamline at the Swiss Light Source has been operational since 2001. In late 2010, the original wiggler source was replaced with a novel insertion device, which allows unprecedented access to high photon energies from an undulator installed in a medium-energy storage ring. In order to best exploit the increased brilliance of this new source, the entire front-end and optics had to be redesigned. In this work, the upgrade of the beamline is described in detail. The tone is didactic, from which it is hoped the reader can adapt the concepts and ideas to his or her needs.

We report on a study of magnetotransport in LaAlO3/SrTiO3 interfaces characterized by mobilities of the order of several thousands cm2/V\,s. We observe Shubnikov\char21{}de Haas oscillations whose period depends only on the perpendicular component of the magnetic field. This observation directly indicates the formation of a two-dimensional electron gas originating from quantum confinement at the interface. From the temperature dependence of the oscillation amplitude we extract an effective carrier mass m*$\simeq${}1.45me. An electric field applied in the back-gate geometry increases the mobility, the carrier density, and the oscillation frequency.

Interplay of spin, charge, orbital and lattice degrees of freedom in oxide heterostructures results in a plethora of fascinating properties, which can be exploited in new generations of electronic devices with enhanced functionalities. The paradigm example is the interface between the two band insulators LaAlO₃ and SrTiO₃ that hosts a two-dimensional electron system. Apart from the mobile charge carriers, this system exhibits a range of intriguing properties such as field effect, superconductivity and ferromagnetism, whose fundamental origins are still debated. Here we use soft-X-ray angle-resolved photoelectron spectroscopy to penetrate through the LaAlO₃ overlayer and access charge carriers at the buried interface. The experimental spectral function directly identifies the interface charge carriers as large polarons, emerging from coupling of charge and lattice degrees of freedom, and involving two phonons of different energy and thermal activity. This phenomenon fundamentally limits the carrier mobility and explains its puzzling drop at high temperatures.

The deployment of Li‐garnet Li₇La₃Zr₂O₁₂ (LLZO) solid‐state electrolytes in solid‐state batteries is severely hampered by their poor wettability with metallic Li. In this work, Sb is presented as a compelling interfacial layer allowing superior wetting of Li onto a LLZO surface, resulting in a remarkably low Li/LLZO interfacial resistance of 4.1(1) Ω cm². An atomistic insight into Sb‐coated LLZO interface using soft and hard X‐ray photoelectron spectroscopy and focused ion beam time‐of‐flight secondary ion mass spectrometry shows the formation of a Li‐Sb alloy as an interlayer. It is determined that the Li/Sb‐coated LLZO/Li symmetrical cells exhibit a high critical current density of up to 0.64 mA cm⁻² and low overpotentials of 40–50 mV at a current density of 0.2 mA cm⁻² without applying external pressure. The electrochemical performance of Sb coated‐LLZO pellets is also assessed with an intercalation‐type V₂O₅ cathode. Li/Sb‐coated‐LLZO/V₂O₅ full cells deliver stable capacities of around 0.45 mAh cm⁻², with a peak current density of 0.3 mA cm⁻².