Federico Bisti

Federico Bisti

Associate Professor in Experimental Condensed Matter Physics

Projects

NavARP Permalink

Published:

NavARP is an open source python project consisting on a companion application during Angle Resolved Photoemission Spectroscopy experiments, and a set of dedicated libraries for deep data analysis. The application has an interactive user interface for exploring the data, enriched by post-processing procedures (e.g. second derivative, Gaussian and Laplacian filters), giving access to the proper band structure axes (k-vectors, binding energy) after a guided transformation from the data acquisition ones (angles, kinetic energy). The so processed and transformed data can be then exported in different format for its inclusion in publications. The same, and more, functionalities are directly accessible in a python object-oriented library extending the possible data analysis work flow.

Many-body effects in Graphene

Published:

The extreme simplicity of its electronic structure has affirmed graphene as an ideal testbed for the demonstration of many-body effects on band structure. Within this context we have investigated: 1) the isotope substitution as an experimental tool to prove the electron-phonon coupling origin of sudden band slope change (known as kink) near the Fermi level; 2) highly doped graphene reaching almost the van-Hove singularity, to demonstrate that its apparent band flattening is just the unoccupied band spectral functional tails.

TOTEM: engineering TOpological quantum phases in hexagonal TErnary coMpounds

Published:

Material hosting quasiparticles acting as Weyl or Dirac fermions offer unique quantum phenomena which could be exploited in a completely new generation of electronic device. These materials are in general called topological semimetals, which differentiate from the topological insulator by hosting directly in the bulk band structure massless excitations, and not only at the surface. In this ongoing project we are characterizing different compounds with aim to discover new topological semimetals and explore the possible tunability of their topological phase by alloy engineering.

SHEEP: Symmetry-broken HEterostructurEs for Photovoltaic applications Permalink

Published:

The idea behind the SHEEP project is to use novel 2D heterostructures that will exhibit the Bulk Photovoltaic Effect (BVPE). Indeed, a “shift current” (the relevant parameter for BPVE generation) occurs every time the real-space centre of charge for valence bands differs from the centre of charge for conduction bands, the results is a photocurrent from the spatial displacement of electrons and holes during light-induced transitions. The SHEEP project is based on a combined theoretical and experimental approach. The engineering of 2D heterostructures will be performed with the use of state-of-the-art computational codes based on density functional theory with advanced functionals, and using the low energy model framework. The SHEEP interfaces will be fabricated via mechanical exfoliation and lift-of and transfer techniques and then further studied with on campus (Raman, PL, STM/STS) and state of the synchrotron radiation tools like micro-ARPES. The project is funded by the European Union – NextGenerationEU (component M4C2, investment 1.1) through the “Ministero dell’Università e della Ricerca” within the program “progetti di ricerca di rilevante interesse nazionale” (PRIN) for the two-year period 2023/2025.