260076 VO Experimental methods in soft matter (2021S)

Soft matter is a term coined roughly 40 years ago by the French scientist Madeleine Veyssié - a strict collaborator of the 1991 Nobel prize in physics PG de Gennes - to include many materials that lie somewhere in-between liquids and solids and that are easily deformed under moderate stresses. Foams, gels, creams, pastes, sludges, dense emulsions, bacterial suspensions, biofilms, membranes, cells, and tissues are just a few examples of soft materials.

As de Gennes himself said in his Nobel lecture: “Americans prefer to call it ‘complex fluids’…a rather ugly name, which tends to discourage the young students”. Soft materials are indeed complex, as they are often the result of the self-organization of basic building blocks, such as polymers, surfactants, and colloidal particles, into more hierarchically organized soft materials. However, they are not necessarily complicated to deal with: theoretically, they can be frequently captured by simple models, dimensional analysis, and scaling laws; numerically, they can be reproduced with conceptually simple tools and efficient algorithms; experimentally, they can be often investigated with unsophisticated experimental setups that reproduce spectacular phenomena and produce revealing and colorful images, movies, and plots. The young student dealing with soft matter is thus not discouraged but, on the contrary, rather excited!

In this course, we focus on the experimental side of the physics of soft matter. You will be introduced to the most important experimental techniques and approaches to poke and probe soft materials. At the end of the course, you will be able to:

- Understand the main properties and applications of the most common experimental techniques/methods to investigate soft matter
- Relate each experimental technique/method to the relevant theoretical principles
- Choose the appropriate technique and experimental approach to study a soft matter system of choice
- Plan an experiment to probe a soft matter system of your choice
- Interpret typical results of experiments on soft materials

During the course, you will learn about modern mechanical and optical techniques that are customarily used to characterized soft materials, e.g. rheology, microrheology, video particle tracking, static and dynamic light scattering, differential dynamic microscopy, diffusing wave spectroscopy, optical tweezers, microfluidics.

TEACHING METHODS:
The course will make use of (online) lectures with slides and whiteboard. In addition, you will learn also through interactive tools (e.g. Kahoot or Mentimeter) and through other tools typical of peer education and collaborative learning (e.g. journal clubs and/or team based learning). Preparation to classroom activities will also benefit from the use of the flipped classroom approach.

PREREQUISITES:
Basic classical physics, including fluid mechanics, optics, thermodynamics, and statistical physics.