EPOSBP project deals with black phosphorus (BP) which has joined the 2D materials family only very recently in 2014. The first representative of this new class of materials is Graphene, isolated ten years ago, which discovery sparkled an intense research activity. However, the lack of band gap in graphene has launched a quest for new 2D materials. The field has gradually been enriched by new contenders such as hexagonal Boron Nitride (hBN) and more recently the transition metal dichalcogenides family (e.g MoS2), leading to the emergence of a broad family of 2D van der Waals materials. In the specific optoelectronic field, the progress has remained limited due to the impossibility to gather together a direct bandgap AND a high carrier mobility within the same material. In this direction, black phosphorus (BP) has attracted an explosive interest since 2014 as it displays major properties for (opto-)electronic devices: (1) high hole and electron mobilities in thin layers of exfoliated BP (~3000 cm2 V-1 s-1). (2) high (~105) ON/OFF current ratio in a transistor configuration with ambipolar characteristics. (3) the BP bandgap is predicted to remain direct from the bulk to the monolayer, making it highly interesting for optical applications. The electronic structure near the Fermi level strongly depends on the number of layers, leading to a bandgap increase from the mid infrared (0.35 eV) in the bulk to the visible range (2 eV) in monolayers. Thus BP offers a unique spectral range in the 2D landscape. However, while early 2017 results seems to highlight BPs peculiar properties in ultrathin layers, only little is known from experimental measurements. Additionally, thanks to its natural low spin-orbit coupling, the BP could be expected to very efficiently preserve the spin lifetime of the carriers, as in graphene, but offering a semiconducting gap. This would be a unique opportunity for spin transport and spintronics. The objective of EPOSBP is to investigate these unique properties of BP and, capitalizing on them, to achieve new optically active flat materials from visible to mid-infrared. The dielectric response as well as the electronic behaviors and spin injection of BP transistor will be investigated to achieve tunable and electrically driven light emission. The project is decomposed into three tasks: 1) learning basics on BP properties aiming at defining a robust spectroscopic tools package for facilitating the integration of BP in devices, 2) fabrication and characterization of devices, 3) fabrication of BP transistors and observation of electroluminescence and efficient spin transport and 4) the demonstration of spin driven light emission. EPOSBP project constitutes a broad partnership that includes the best specialists and skills on 2D Black Phosphorus and Spintronics allied with specialists of most advanced relevant spectroscopic characterization techniques, integration of 2D materials in devices and specialists capable to demonstrate the potential of BP for innovative electroluminescence and tunable spin transport devices. The strong commitment of industrial partner Thales, with key interests in the semi-conductor area, is a strong enabler toward potential TRL rise of the project.

Fifty years of dramatic advances in microelectronics have reshaped the way we communicate and work, but progress on silicon-based technologies could well be reaching their limits. This calls for fresh research on new materials for the electronic industry. In this context, fabrication of high quality oxide heterostructures (HS) lies at the heart of the emerging field of oxide electronics. Indeed, Ohtomo and Hwang (2004) have shown that a two dimensional electron gas (2DEG) can be formed in HS based on the wide-gap band insulator SrTiO3 (STO). This is appealing, as STO is a member of the transition metal oxides (TMOs). These materials present unique properties, such as high temperature superconductivity in cuprates, colossal magnetoresistance in manganites, multiferroic behaviour in bismuth ferrites. Owing to their similar perovskite structure, one can combine them into a large variety of HS, hoping for novel emerging properties at their interfaces. A recent breakthrough due to the Coordinator and several members on this project may open a new way to create and study 2DEGs in TMOs: we found that a 2DEG can be obtained at the bare surface of insulating STO by simply fracturing a crystalline sample in vacuum. An exciting perspective, which is at the core of the present proposal, is that the underpinning mechanism of such a 2DEG may be generic to other perovskites, and that the ensuing 2DEGs might inherit some of the properties of their host compounds, which are often correlated electron systems. Thus, we will aim at the creation and engineering of novel 2D electronic states at the surface of TMOs endowed with technologically promising functionalities. Materials to be investigated include the ferroelectric BaTiO3 (BTO), as well as manganites and multiferroics, which could present strongly spin-polarized 2DEGs allowing the creation of electrically controllable spintronic devices. Furthermore, very recent results from our consortium suggest original routes to craft non-trivial topological states in oxide surfaces. In this project, we will explore the realization of new topological 2DEGs at the surface of TMOs. Moreover, in order to search for optimal or new functionalities, we will tailor in-situ their microscopic properties, like carrier density, spin-orbit or spin-spin interactions, and directly follow the evolution of their electronic structure. At the core of our strategy, we will use a combination of state-of-the-art in-situ preparation and characterization techniques and photoemission spectroscopy. Understanding such surface metallic states requires detailed studies of the role of oxygen vacancies created during the fracturing process. Key issues to be addressed include identifying the mechanisms that can form, stabilize and allow an engineering of the oxygen vacancies at the surface of TMOs. Furthermore, we will find ways to protect the surface 2DEGs to render them usable for transport measurements and for applications. This project is a re-submission of our project “LACUNES”. We have taken into account the remarks made by the Evaluation Committee, and made sure to allay their concerns. Outcomes of this project can open new avenues for the development of electronics based on TMOs. The consortium combines the necessary skills to meet the challenges of the present proposal, as our recent experimental/theoretical collaboration shows. Our discovery and recent preliminary results, described below, demonstrate the feasibility and potential of our approach to create novel 2DEGs in several TMOs.

MIXES is a collaborative research project that explores the fundamental structural and electronic properties of novel 2D-0D nanomaterial, made of 2D materials in interaction with self-ordered nanoclusters grown using dry methods compatible with microelectronics industry processes. First results show that these nanomaterials, once implemented into tunnel junctions, demonstrate robust Coulomb blockade oscillations and magneto-Coulomb properties, preserved on device being 6 orders of magnitude larger than usual single-electron devices. These results have raised questions regarding the underlying fundamental physics that are addressed by this project. In particular, we will address the following fundamental questions: i) What is the chemical/structural/electronic nature of the 2D/0D interface? How are the local/extended structural and electronic properties of 2D/0D nanomaterials influenced by the nature of the 2D/0D interface, when it varies from van der Waals type to covalently bound ? (ii) What is the key mechanism behind many dissimilar nanoclusters apparently behaving as single or identical entities in the 2D-0D nanomaterial? How can it be mastered for simple and large-scale processing of a single electron device? iii) Can it be extended to other 2D materials such as dichalcogenic transition metals? iv) How can these properties be used to create new single electron multifunctional devices? We follow an interdisciplinary approach covering ab-initio modelling, surface science, structural analysis, nanofabrication and transport measurements. We keep as final goal to use these new knowledges to build novel architecture of multifunctional single-electron electronics and spintronics devices, operating up to room temperature.

The innovative objective of the TRINIDAD project is to extend to the microwave frequency range the concept of doped transmission used by optical telecommunication. A first aim is to develop within a 24 months period a loss-compensated spin-wave propagation medium. A second aim is to pattern this medium into a micron-size wave guide in order to achieve an analog delay line of unprecedented quality and integrable into the future electronics. The core idea of TRINIDAD is to join a magnetic insulator and a normal metal. In such a double-layered structure the magnetic insulator – Yttrium-Iron Garnet (YIG) – provides a low-loss propagation medium where an input microwave electromagnetic signal is converted into a slowly propagating spin-wave. A first key property of the targeted device is the use of ultra-thin films of YIG in order to reduce the group velocity of the spin-wave below 10m/s. A second key property is that intrinsic losses of the traveling spin-wave are partially or even fully compensated allowing the delay time to be increased beyond the natural spin-wave decay, which presently is a key issue that limits this technology. The oscillatory signal will be amplified by an injected flow of angular momentum (or pure spin current) from an out-of-equilibrium spin accumulation layer produced by the electrons moving in an adjacent metallic layer. The spin current will be created by the spin-Hall effect (requires strong spin-orbit metals or alloys: e.g. Pt, Ta or CuIr and AuW). The net result of the spin current will be to amplify (or to reduce, depending on the sign of the applied current) the propagating signal by the process of stimulated emission at the metal/insulator interface. Delays of few microseconds could then be potentially achieved over micrometer distances. In the future, such delay line could be used as the elementary building block for other high performance microwave devices such as an ultra-low phase noise oscillator or a voltage controlled tunable filter. Target applications lie in radar and telecommunication technology, which are looking for electronically tuned ultra-narrow band, non-reciprocal devices, combining both high-agility and ultra-narrow selectivity.

The advent of femtosecond lasers in the field of solid state physics has been at the origin of many discoveries. For instance, in the field of magnetism it was possible in the last decade to understand how femtosecond optical demagnetization can probe the exchange interaction in ferromagnetic metals. The core of the UltrAMOX proposal is to explore how optically generated ultrafast acoustic waves interact with the magnetization of a thin film, and vice versa, how femtosecond demagnetization can lead to longitudinal and shear acoustic waves excitation from the release of magnetostrictive stresses. The later relevant physical framework is known as direct magnetostriction, which is the property of ferromagnetic materials that causes them to change their shape or dimensions during the process of magnetization or demagnetization. The reverse phenomenon appears when an applied external stress modifies statically or dynamically the magnetization configuration of a ferromagnet. A number of novel interesting physical phenomena can be expected to arise when an ultrafast acoustic pulse, excited through absorption of a femtosecond laser pulse at a photoacoustic transducer, is injected through a ferromagnetic sample (for instance a thin ferromagnetic film or a nanostructured array of ferromagnets). Under some specific conditions that have to be clearly identified, this generic idea termed "acousto- spintronics" could allow for ultrafast magnetization manipulation. Reversely, ultrafast demagnetization of magnetostrictive ferromagnets from femtosecond laser pulses is expected to release ultrafast acoustic pulses that carry out crucial information on the onset of spin-lattice coupling. The UltrAMOX project is a three-year fundamental and experimental project in which we aim to address the phenomena of direct and inverse laser mediated ultrafast magnetostriction in ferromagnets relevant to spintronics. We propose to merge picosecond ultrasonics where femtosecond lasers are used to excite ultrafast acoustic pulses, with femtomagnetism and spintronics. The goals of UltrAMOX project are twofold and can be listed as following: 1) Direct ultrafast magnetostriction: Investigation of the generation of THz longitudinal and shear acoustic pulses through laser mediated release of magnetostrictive stresses in ferromagnetic compounds. 2) Inverse ultrafast magnetostriction: Investigation of ultrafast interaction of laser generated ultrasonic pulses with spins and magnons in hybrid metal/ferromagnet multilayer structures.