Modelling of functional materials

It is widely recognized that the development of disruptive technologies – in fields that range from ultralow-power electronics to novel in-memory computing paradigms, from quantum technologies to energy harvesting and storage – will rely on the development of low cost, eco-friendly materials with tailor-made properties optimized for specific applications. It is also generally acknowledged that, in order to accelerate progress, experimental and engineering work must be supplemented with theoretical understanding and numerical modelling. On the one hand, theoretical and modelling work reveal the physical and chemical mechanisms responsible for the properties of interest, leading to better-informed hypotheses for further discoveries or material optimizations. On the other hand, predictive numerical modelling based on quantum-mechanical theory – and increasingly aided by modern machine-learning techniques – can test the performance of hypothetical (nano)materials, including composite and nanostructured systems, and thus deliver useful predictions to guide experimental efforts.

Objectives

The Modelling of Functional Materials group  develops and applies advanced theoretical and simulation methodologies for understanding and optimizing advanced functional materials, predict the properties of even hypothetical compounds and support broad range of applications. In line with the focus of its unit and the Institute, current activities  focuses on functional oxides, especially materials that can be used for a variety of transducing applications – i.e. the transformation of one form of energy (e.g. elastic or thermal) into another (e.g. magnetic or electric). In particular, the group specializes in ultra-reactive and highly tuneable materials (e.g. ferroelectrics and magnetoelectric multiferroics)  that are already used in  applications ranging from frequency filters for wireless communications to medical tools like ultrasound equipment, and which hold promise for disruptive innovations in fields such as catalysis, electronics and computing.

The mission of the group is thus multi-fold, with the following general objectives:

• Supporting the experimental work and technological developments of LIST groups – or external partners, including industries – who can benefit from predictive theoretical and simulation methods.
• Improving the basic understanding of novel ferroelectric and multiferroic materials of definite technological interest, identifying directions for their further optimization.
• Developing predictive theoretical and simulation methods that address the materials’ performance under device-operation conditions, often pushing the state of the art of numerical material modelling.

Scope of expertise

To tackle these objectives, the Modelling of Functional Materials brings together recognized world-class experts in the following areas:

• Ferroelectric materials – including nanostructures, the physics of phase transitions, anomalous properties such as the so-called “negative capacitance” response, and a  variety of associated functional responses and their optimization (pyroelectric and electrocaloric, piezoelectric and electrostrictive, capacitive and memristive, static and dynamic). Expertise also extends to novel electric topological phases of potential application, e.g. in novel concepts for in-memory computing.
• Magnetoelectric multiferroic materials – including the physical description and optimization of materials whose magnetic state and properties can be controlled electrically, and of potential application in the development of ultralow-power memories (e.g. by controlling the net magnetization electrically) or spintronic logic devices (e.g. by controlling the magnon propagation electrically).
• Novel silicon-compatible ferroelectrics – including HfO2 and ZrO2-based fluorite compounds, which offer an eco- (lead-free) electronic-friendly alternative to the better-known ferroelectric perovskite compounds. The group leads the global effort to decipher the physical and chemical mechanisms responsible for the unusual ferroic properties of fluorite ferroelectrics, developing simulation strategies that address both the intrinsic and extrinsic effects at play.
• Nanostructured materials and interfaces – including thin films and heterostructures (e.g. superlattices) where the properties of the compounds are strongly influenced (can be significantly controlled and enhanced) by elastic and electric boundary conditions. MFM’s work is progressively evolving towards an explicit consideration of interfacial phenomena (e.g. ferroelectric-metal interface), which is necessary to address the factors conditioning the optimization of realistic nano-devices.
• Other functional materials and properties - Besides the traditional effects associated with ferroelectrics (very high and tuneable properties, including dielectric, piezoelectric, pyroelectric and electrooptic) and multiferroics (magnetoelectric response, electrically controllable magnetism), the group’s expertise extends to many other functional properties and materials of interest, including transport (electric, heat), catalysis (with an incipient activity focused on water splitting) and 2D materials.

To conduct their research, the group members develop and/or use a variety of state-of-the-art theoretical and simulation techniques:

• First-principle quantum-mechanical methods – typically based on density functional theory and adapted, providing predictive power to help understand experiments and predict the properties of new or optimized (nano)material combinations.
• Effective models for larger-scale simulations – including the development and application of methods for medium-scale (~104 atoms, ~10 ns) and large-scale (~1010 atoms, ~1 ms) simulations, as well as phenomenological theories that provide physical insights into diverse complex phenomena.
• Machine-learning methods – with a strategy to remain at the forefront of this rapidly expanding field, readily adopting ML methods for the development of effective models and the analysis of large datasets, among others.

Open for partnerships and collaborations!

The Modelling of Functional Materials has a long track record of trustworthy and successful collaborations with academic and industrial partners. Its expertise s provides valuable input for research, technology development and innovation. The group regularly partners on collaborative projects at European and international levels. If your have a project idea where you think the group could make a difference, please reach out!