**Email**

sebastiano{dot}peotta{@}aalto{dot}fi

**Mailing address**

Department of Applied Physics

Aalto University

PL 15100

FI-00076 Aalto

Finland

**ORCID ID:** orcid.org/0000-0002-9947-1261

**Researcher ID:** C-4856-2015

I obtained my PhD in 2013 at Scuola Normale Superiore di Pisa with a thesis on out of equilibrium dynamics of many-body quantum systems. Then I moved for two years to San Diego in United States to work in the group of prof. Massimiliano Di Ventra. There I studied the transport properties of ultracold gases and superconducting weak-links. From the beginning of 2015 I am working in prof. Päivi Törmä Quantum Dynamics (QD) group at Aalto University, Finland, and my main research topic is flat Bloch bands with connections to high temperature superconductivity and topological phases of matter. In 2016 I have been awarded a Marie Skłodowska-Curie Fellowship which lasted until March 2018 and has been carried out in the QD group. The name of the project is FLATOPS "Flat bands, topology and superconductivity".

The foundations of **quantum mechanics** were laid down almost one century ago, but it is still a topic of active research. We know the fundamental equations governing matter at the microscopic level (Schrödinger equation, Dirac equation, Standard Model, etc.) and these can predict with astonishing accuracy the properties of few-particle ensembles, for example the hydrogen atom emission spectrum. However things get difficult when a large, macroscopic, number of particles is involved and this is precisely the realm of **condensed matter physics**, whose ultimate goal is to predict the properties of materials starting from the atomic structure. It turns out that the equations of quantum mechanics are extremely difficult to solve, namely the effort required for their solution grows exponentially with the size of the system under study.

Although a definitive answer to this "**exponential wall**" problem has not been given yet, many ingenious techniques have been developed over the years to overcome it. I have been working extensively with a numerical method called **Density Matrix Renormalization Group** which is especially useful for **one-dimensional quantum many-body systems**. I used this method to study a number of phenomena relevant for experiments in **ultracold gases**, which are arguably the simplest, yet nontrivial, quantum mechanical systems defying our theoretical understanding.

A recurrent subject of my research is **superconductivity**, **superfluidity** and the **Josephson effect**, important examples of **macroscopic quantum effects**. Together with prof. Massimiliano Di Ventra I have proposed an implementation of a **superconducting memristor** using Josephson junctions. More recently in prof. Törmä group I became interested in the transport properties of **flat bands**. It has been predicted that flat bands can enhance dramatically the critical temperature of the superconducting transition which is very desiderable for practical applications. Together with prof. Törmä I discovered a novel connection between superfluidity and the **geometric and topological properties** of the **band structure**. These results may provide an explanation for the puzzling behavior of known **high-temperature superconductors**.

More details can be found in my **publications**.

The route to high temperature superconductivity goes through the flat band, November 20th 2015.

My research highlighted in Helsingin Sanomat in occasion of prof. Törmä Academy Professorship (in Finnish), August 26th 2016.

Quantum dynamics group of prof. Päivi Törmä

prof. Massimiliano Di Ventra group at University of California San Diego, United States

Condensed Matter and Quantum Information Theory group at Scuola Normale Superiore di Pisa, Italy