Physics of surfaces, interfaces and hybrid materials
The Surface and Interface Physics group studies interfacial phenomena primarily involving liquids confined in micro- and nanostructures, which are characterized by a high surface-to-volume ratio. Specifically, the group focusses on microfabrication, droplet microfluidics, wettability, nanotribology, optical properties of two-dimensional materials, and the development of optical systems for soft matter and microfluidics experiments.
Staff
Full Professors:Giampaolo Mistura, Cinzia Sada
Associate Professors: Michele Merano, Matteo Pierno
Assistant Professors: Davide Ferraro, Daniele Filippi, Annamaria Zaltron
Technical staff: Nicola Argiolas, Luca Bacci, Giorgio Delfitto, Carlo Scian
Post-doc
Alessio Meggiolaro, Chiara Maceri, Valentina Moccia, Noemi Torriero
PhD students
Daniele Andrean, Giovanni Bragato, Leonardo Cobelli, Sebastian Cremaschini, Beatrice Crestani, Andrea De Marco, Filippo Marinello, Giovanni Piccolo
Research activities
Droplet microfluidics
Microfluidics is the science that studies how to manipulate small amounts of liquids (from µL to fL) using channels with micrometric dimensions (ranging from 10 to 100 µm). The small size of these channels ensures laminar flow, providing excellent control of the motion of confined liquids. Droplet microfluidics involves the generation of controlled emulsions between two or more immiscible phases using microfluidic channels. In these systems, each droplet can be considered an independent micro-reactor, separate from other droplets and the surrounding environment. For this reason, droplet microfluidics is rapidly expanding, offering applications in chemistry and biology, as well as providing a flexible platform for fundamental studies of complex systems. Specifically, we focus on the creation of emulsions for fundamental studies of droplet behavior in confined systems and for biomedical applications, such as the isolation of extracellular vesicles.
Contacts: Giampaolo Mistura, Davide Ferraro, Matteo Pierno
Wettability of engineered surfaces
The wettability of a surface is a fundamental phenomenon in interface physics concerning the shape and motion of droplets deposited on a surface. In general, by acting on the chemistry and physics of surfaces, it is possible to control the movement of liquids. For example, droplets can be confined to defined regions of a surface or, conversely, their movement can be facilitated by reducing friction using lubricated surfaces (Lubricant-Infused Surfaces), which are widespread in various application fields. Additionally, the movement of droplets can be controlled through active methods, such as the application of electrical, magnetic, or optical fields or mechanical oscillations. Specifically, we study these phenomena from both fundamental and applied perspectives.
Contacts: Giampaolo Mistura
Materials for Integrated Optics
The research activity is focused on new materials and associated characterisation of physical properties for applications in advanced optics, with particular emphasis on unconventional approaches for selective optical sensing of molecules, gases and aggregates, and biological elements. Interest is directed towards the development of inorganic/organic hybrid materials whose configurability and modularity can be scaled up into multifunctional platforms that exploit the potential of integrated optics and the diverse optical response promoted by compositional, morphological and even photo-induced changes on such materials.
Contacts: Cinzia Sada
Soft Matter
What ‘soft matter’ is, it was well explained in the 1991 Nobel Lecture of Pierre-Gilles de Gennes, referring to ‘molecular systems that give a strong response to a very weak command signal’. In short, they are easily deformed by thermal fluctuations and external forces.
Examples of soft materials include colloidal suspensions, polymers, macromolecules, liquid crystals, and emulsions. Therefore, their building blocks are in the mesoscopic spatial scale, i.e. intermediate in size between atoms and grains, and this is crucial to understanding their behavior.
We are interested in unraveling the mechanisms of yielding and flow of soft glassy materials, such as concentrated emulsions. In particular, we focus on microfluidic confinement, where boundary conditions can definitely alter the fluidization, diffusion, and rheological response under confinement.
Similarly, we also consider how microfluidic geometries influence the motility patterns of self-propelled systems, like bacterial populations, i.e. soft materials that convert in motion a certain amount of their stored internal energy.
Contacts: Matteo Pierno
Nano- and micro-tribology
Tribology is the science that studies friction between two contacting systems and involves various application and research fields, including engineering, materials science, chemistry, physics, and nanotechnology. Despite its importance, several fundamental physical aspects of dissipative phenomena in tribology are still not fully understood or investigated. This is due to their complexity, which is related to nonlinear and out-of-equilibrium processes, as well as the difficulty in creating model interfaces. Specifically, we study the tribological behavior of two-dimensional model systems across different spatial and temporal scales: from the sliding of atomic or molecular films using a quartz crystal microbalance to the dynamics of microfluidic crystals using optofluidic techniques.
Contacts: Giampaolo Mistura, Matteo Pierno
Functional Optofluidic platforms in Lithium Niobate
The research activity is focused on the development of new opto-microfluidic platforms on lithium niobate crystals for studying physical phenomena in confined sub-millimeter and micrometer-sized systems, such as droplets. Particular attention is given to understanding and describing the chemical-physical properties of these systems and their response to photo-induced effects as their composition varies. This research also has applications in detecting dispersed species in the form of aggregates, which are of interest in contamination and environmental pollution analysis.
Contacts: Cinzia Sada
Optical properties of 2D materials and heterostructures
Two-dimensional (2D) crystals are a new class of materials with a great impact on science and technology. They promise plenty of possible applications and challenges the scientists for a deep comprehension of their physical properties. We investigate experimentally the optical response of 2D crystals with both fundamental and applicative final goals.
Contacts: Michele Merano
