Monolayer Magnetic Metal with Scalable Conductivity.

2D magnets have emerged as a class of materials highly promising for studies of quantum phenomena and applications in ultra-compact spintronics. Current research aims at design of 2D magnets with particular functional properties. A formidable challenge is to produce metallic monolayers: the material landscape of layered magnetic systems is strongly dominated by insulators; rare metallic magnets, such as FeGeTe, become insulating as they approach the monolayer limit.

Magnetic polarons reach a hundred thousand Bohr magnetons.

The ability of light to manipulate fundamental interactions in a medium is central to research in optomagnetism and applications in electronics. A prospective approach is to create composite quasiparticles, magnetic polarons, highly susceptible to external stimuli. To control magnetic and transport properties by weak magnetic and electric fields, it is important to find materials that support photoinduced magnetic polarons with colossal net magnetic moments.

Emerging 2D Ferromagnetism in Graphenized GdAlSi.

2D magnets are expected to give new insights into the fundamentals of magnetism, host novel quantum phases, and foster development of ultra-compact spintronics. However, the scarcity of 2D magnets often makes a bottleneck in the research efforts, prompting the search for new magnetic systems and synthetic routes. Here, an unconventional approach is adopted to the problem, graphenization - stabilization of layered honeycomb materials in the 2D limit.

Engineering of a Layered Ferromagnet via Graphitization: An Overlooked Polymorph of GdAlSi.

Layered magnets are stand-out materials because of their range of functional properties that can be controlled by external stimuli. Regretfully, the class of such compounds is rather narrow, prompting the search for new members. Graphitization─stabilization of layered graphitic structures in the 2D limit─is being discussed for cubic materials.

Mapping the phase-separated state in a 2D magnet.

Intrinsic 2D magnets have recently been established as a playground for studies on fundamentals of magnetism, quantum phases, and spintronic applications. The inherent instability at low dimensionality often results in coexistence and/or competition of different magnetic orders. Such instability of magnetic ordering may manifest itself as phase-separated states.

Thickness-Dependent Superconductivity in a Layered Electride on Silicon.

Layered materials exhibit a plethora of fascinating properties. The challenge is to make the materials into epitaxial films, preferably integrated with mature technological platforms to facilitate their potential applications. Progress in this direction can establish the film thickness as a valuable parameter to control various phenomena, superconductivity in particular.

Intrinsic exchange bias state in silicene and germanene materials EuX.

2D magnets have recently emerged as a host for unconventional phases and related phenomena. The prominence of 2D magnetism stems from its high amenability to external stimuli and structural variations. The low dimensionality facilitates competition between magnetic orders which may give rise to exchange bias, in particular in magnetic heterostructures.

Proximity Coupling of Graphene to a Submonolayer 2D Magnet.

Imprinting magnetism into graphene may lead to unconventional electron states and enable the design of spin logic devices with low power consumption. The ongoing active development of 2D magnets suggests their coupling with graphene to induce spin-dependent properties via proximity effects. In particular, the recent discovery of submonolayer 2D magnets on surfaces of industrial semiconductors provides an opportunity to magnetize graphene coupled with silicon.

Femtosecond optical orientation triggering magnetization precession in epitaxial EuO films.

Light-induced magnetization response unfolding on a temporal scale down to femtoseconds presents a way to convey information spin manipulation. The advancement of the field requires exploration of new materials implementing various mechanisms for ultrafast magnetization dynamics. Here, pump-probe measurements of EuO-based ferromagnets by a time-resolved two-colour stroboscopic technique are reported.

Exchange Bias State at the Crossover to 2D Ferromagnetism.

The inherent malleability of 2D magnetism provides access to unconventional quantum phases, in particular those with coexisting magnetic orders. Incidentally, in a number of materials, the magnetic state in the bulk undergoes a fundamental change when the system is pushed to the monolayer limit. Therefore, a competition of magnetic states can be expected in the crossover region.

Layer-controlled evolution of electron state in the silicene intercalation compound SrSi.

Silicene, a Si-based analogue of graphene, holds a high promise for electronics because of its exceptional properties but a high chemical reactivity makes it a very challenging material to work with. The silicene lattice can be stabilized by active metals to form stoichiometric compounds MSi. Being candidate topological semimetals, these materials provide an opportunity to probe layer dependence of unconventional electronic structures.

2D magnetic phases of Eu on Ge(110).

2D magnetic materials are at the forefront of research on fundamentals of magnetism; they exhibit unconventional phases and properties controlled by external stimuli. 2D magnets offer a solution to the problem of miniaturization of spintronic devices. A technological target of materials science is to find suitable magnetic materials and scale their thickness down as much as possible, a single monolayer being a natural limit.

High Carrier Mobility in a Layered Antiferromagnet Integrated with Silicon.

Coupling various functional properties in one material is always a challenge, more so if the material should be nanostructured for practical applications. Magnetism and high carrier mobility are key components for spintronic applications but rather difficult to bundle together. Here, we establish EuAlSi as a layered antiferromagnet supporting high carrier mobility.

Two-Dimensional Magnets beyond the Monolayer Limit.

Intrinsic two-dimensional (2D) magnetism has been demonstrated in various materials scaled down to a single monolayer. However, the question is whether 2D magnetism extends beyond the monolayer limit, to chemical species formed by sparse but regular 2D arrays of magnetic atoms. Here we show that sub-monolayer superstructures of Eu atoms self-assembled on the silicon surface exhibit strong magnetic signals.

Interface-Induced Anomalous Hall Conductivity in a Confined Metal.

The mature silicon technological platform is actively explored for spintronic applications. Metal silicides are an integral part of the Si technology used as interconnects, gate electrodes, and diffusion barriers; their epitaxial integration with Si results in premier contacts. Recent studies highlight the exceptional role of electronic discontinuities at interfaces in the spin-dependent transport properties.

High-Temperature Magnetism in Graphene Induced by Proximity to EuO.

Addition of magnetism to spectacular properties of graphene may lead to novel topological states and design of spin logic devices enjoying low power consumption. A significant progress is made in defect-induced magnetism in graphene-selective elimination of p orbitals (by vacancies or adatoms) at triangular sublattices tailors graphene magnetism. Proximity to a magnetic insulator is a less invasive way, which is being actively explored now.

Emerging two-dimensional ferromagnetism in silicene materials.

The appeal of ultra-compact spintronics drives intense research on magnetism in low-dimensional materials. Recent years have witnessed remarkable progress in engineering two-dimensional (2D) magnetism via defects, edges, adatoms, and magnetic proximity. However, intrinsic 2D ferromagnetism remained elusive until recent discovery of out-of-plane magneto-optical response in Cr-based layers, stimulating the search for 2D magnets with tunable and diverse properties.

Fine structure of metal-insulator transition in EuO resolved by doping engineering.

Metal-insulator transitions (MITs) offer new functionalities for nanoelectronics. However, ongoing attempts to control the resistivity by external stimuli are hindered by strong coupling of spin, charge, orbital and lattice degrees of freedom. This difficulty presents a quest for materials which exhibit MIT caused by a single degree of freedom.

Europium Silicide - a Prospective Material for Contacts with Silicon.

Metal-silicon junctions are crucial to the operation of semiconductor devices: aggressive scaling demands low-resistive metallic terminals to replace high-doped silicon in transistors. It suggests an efficient charge injection through a low Schottky barrier between a metal and Si. Tremendous efforts invested into engineering metal-silicon junctions reveal the major role of chemical bonding at the interface: premier contacts entail epitaxial integration of metal silicides with Si.

Anomalous Hall effect in the prospective spintronic material Eu1-x Gd x O integrated with Si.

Remarkable properties of EuO make it a versatile spintronic material. Despite numerous experimental and theoretical studies of EuO, little is known about the anomalous Hall effect in this ferromagnet. So far, the effect has not been observed in bulk EuO, though has been detected in EuO films with uncontrolled distribution of defects.