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Modern technology such as electronics and photovoltaics requires careful control of optical responses of electronic properties. Here, Sando et al. demonstrate a large variation of optical index and light absorption in multiferroic material BiFeO₃thin films, tunable by in-film strain or electric field.

Ferroelectric organic materials can be used for tunnel barriers in memory devices as a cheaper and eco-friendly replacement of their inorganic counterparts. Here, Tian et al. use poly(vinylidene fluoride) with 1–2 layer thickness to achieve giant tunnel electroresistance of 1,000% at room temperature.

The thin highly conducting electron layer at the interface of LaAlO₃ grown on SrTiO₃ is of promise for nanoscale electronics. Here, the authors show that, by depositing a thin cobalt film on top of LaAlO₃, the minimum thickness of LaAlO₃needed for this conducting layer to form can be reduced to one unit cell.

A quantum point contact formed in the two-dimensional electron gas of a LaAlO₃/SrTiO₃ interface exhibits quantized conductance due to ballistic transport in a controllable number of one-dimensional conducting channels.

Electric-field-induced switching of material’s magnetization is a promising approach for achieving energy-efficient memory devices. By taking advantage of the strong magnetoelectric coupling with a BaTiO₃ substrate, a small electric field is used to switch a FeRh thin film from anti- to ferromagnetic above room temperature.

Visualization of the Rashbasplit bands in oxide two-dimensional electron gases is lacking, which hampers understanding of their rich spin-orbit physics. Here, the authors investigate KTaO₃ two dimensional electron gases and their Rashba-split bands.

Induced magnetic ordering at complex oxide interfaces holds potential for spintronic applications. Here, Bruno et al.image the imprinting of domains between ferromagnetic and antiferromagnetic thin films in oxide heterostructures, and demonstrate the effects on tunnelling magnetotransport.

The polarization direction of a ferroelectric-like state can be used to control the conversion of spin currents into charge currents at the surface of strontium titanate, a non-magnetic oxide.

A very large spin-to-charge conversion arising from a combination of the Rashba effect and topologically non-trivial states is realized at the interface of strontium titanate and aluminium, with implications for the role of topology in memory and transistor designs.

The electronic properties of oxide interfaces are renowned for their richness. A comprehensive study of a series of perovskite nickelates examines the interplay between charge transfer and hybridization effects.

The Rashba effect at the LaAlO₃/SrTiO₃ interface is shown to enable large and gate-tunable spin-to-charge conversion through the inverse Rashba–Edelstein effect.The spin current is injected, through spin pumping, from a NiFe film.

The ferroelectric properties of BiFeO₃ have been the subject of extensive study. Using a range of experimental tools and numerical modelling, it is now shown that its ferroic properties can also be manipulated by strain effects, giving rise to a variety of magnonic phenomena.

With only a few known useful room-temperature multiferroics, other ways of achieving materials showing magnetism as well as electrical polarization are sought. The discovery that the ferroelectric BaTiO₃ also shows magnetism at room temperature at the interface with iron or cobalt marks a new approach to achieving multiferroic properties.

A central goal of spintronics is electric control of magnetism. One particularly promising method makes use of spin-orbit torques which arise due to the combination of electric current, and the intrinsic spin-orbit effect in a material. Here, Grezes et al demonstrate non-volatile electrical control of the spin-orbit torque generated at the interface between an oxide and a metal.

Magnons are collective excitations of spins in a material, and just like individual electron spins, they could form the basis for novel computing concepts. Now, determination of the almost loss-less electrical switching of magnons at room temperature takes us a step closer to such ‘magnonic’ devices.

The penetration of a superconducting current from a superconductor into a half-metallic ferromagnet is usually forbidden. Resonances in the conductance spectra of superconductor/half-metal heterostructures suggest this restriction is lifted by the occurrence of unconventional equal-spin Andreev reflection.

The anomalous Hall effect (AHE) occurs in ferromagnets caused by intrinsic and extrinsic mechanisms. Here, Yoo et al. report large anomalous Hall conductivity and Hall angle at the interface between a ferromagnet La_0.7Sr_0.3MnO₃ and a semimetallic SrIrO₃, due to the interplay between correlated physics and topological phenomena.

Control of magnetism by an electric field is of interest for applications such as information storage. Here, the authors achieve this magnetoelectric coupling in a non-superconducting cuprate, sandwiched between two ferromagnetic manganese oxide layers, whose magnetization can be switched with the sole action of an electric field.

The nature of the doping dependent superconducting transition remains elusive for a two dimensional electron gas at the LaAlO₃/SrTiO₃ interface. Here, Singh et al. report superfluid stiffness and the superconducting gap energy at such interface as a function of carrier density.

Heterostructures based on (111)-oriented KTaO₃crystals are a new platform for studying oxide interfaces. Gate-tunable superconductivity in 2D electron gases at the surface of (111)-oriented KTaO₃is now reported, with the superconducting transition being of the Berezinskii-Kosterlitz-Thouless type.

Tailoring antiferromagnetic domains is critical for the development of low-dissipative spintronic and magnonic devices. Here the authors demonstrate the control of antiferromagnetic spin textures in multiferroic bismuth ferrite thin films using strain and electric fields.

The interfaces between some perovskite oxide insulators show spectacular electronic properties, originating from the formation of an electron gas. The spatial extent of the electron gas is still under debate. Conducting tip atomic force microscopy is now used to show that, depending on the growth conditions, the high-mobility electron gas can extend to hundreds of micrometres or to just a few nanometres from the interface.

As alternative technologies for non-volatile memory elements are looked at, the utilization of ferroelectric layers to read-write upon is seen as promising. However, it is plagued by several problems, including a destructive readout process. Now, by using a thin layer of BaTiO₃ put under intense strain, it has been shown possible to read out the polarization state of the material without destroying it.

The variety of emergent phenomena occurring at oxide interfaces has made these systems the focus of intense study in recent years. We argue that spin–orbit effects in oxide interfaces provide a versatile handle to generate, control and convert spin currents, with a view towards low-power spintronics.

The labyrinthine domain patterns formed in ultrathin films of ferroelectric oxides by subcritical quenching undergo an inverse phase transition to the less-symmetric parallel-stripe domain structure upon increasing temperature.

The thermodynamic properties of magnetocaloric materials show significant promise for energy-efficient cooling applications. The demonstration that large and reversible magnetocaloric effects can be created by means of strain suggests a new approach for inducing them in other magnetic materials.

A non-invasive scanning magnetometer, based on a single nitrogen–vacancy defect in diamond, visualizes antiferromagnetic order at the nanometre scale in thin films of bismuth ferrite at room temperature.

Chiral electric and magnetic structures are observed at domain walls in thin films of the room-temperature multiferroic BiFeO₃.

An exotic two-dimensional electron gas (2DEG) forms at oxide interfaces based on SrTiO₃, but the precise nature of the 2DEG has remained elusive. In a systematic study using angle-resolved photoemission spectroscopy (ARPES), new insights into the electronic structure of the 2DEG are obtained. The findings shed light on previous observations in SrTiO₃-based heterostructures and suggest that different forms of electron confinement at the surface of SrTiO₃ lead to essentially the same 2DEG.

Sub-coercive electric fields and sub-picosecond light pulses are shown to enable low-power manipulation of antiferromagnetic domains in the multiferroic BiFeO₃.

A large 'magnetoresistance' signal is observed in a system that combines a carbon nanotube as the channel for spin-polarized current with electrodes made from manganite, and shows that spin-polarized electrons are efficiently injected from manganite to nanotube and also efficiently transported through the nanotube channel.

The underlying mechanisms of the metal-insulator transition in correlated oxides are a rich source of interesting physics and a topic of long-standing investigation. Here, the authors use angle-resolved photoelectron spectroscopy to investigate changes in charge carrier properties and electron-phonon interactions as a function of Ce-doping across the metal-insulator transition in CaMnO3.

The electronic properties of complex oxide heterostructures are governed by the physics at the interface between the different materials. Here, the authors use infrared ellipsometry and confocal Raman spectroscopy to show the presence of non-collinear and asymmetric interfacial polar moments in SrTiO₃-based heterostructures underlying the important role of oxygen vacancies in these systems.