Exciton-phonon interaction in semiconductors: theory, coding and applications

Add to your list(s) Download to your calendar using vCal

• Dr Fulvio Paleari (CNR Istituto Nanoscienze, Modena)
• Wednesday 05 November 2025, 14:00-15:30
• Seminar Room 3, RDC.

If you have a question about this talk, please contact Bo Peng.

The problem of exciton-phonon interaction in crystals concerns the simultaneous description of the interaction of excited electron-hole pairs both with themselves and with lattice vibrations. It has become increasingly relevant to both experimental and theoretical research. It is invoked, for example, to explain fine structures in optical absorption and luminescence spectra of low-dimensional semiconductors, to model the width of excitonic spectral peaks, and to explain the out-of-equilibrium carrier dynamics in ultrafast spectroscopy in terms of lifetimes and intervalley scatterings. I will first briefly introduce the concepts of phonons and excitons from a many-body point of view and in the context of ab initio, first-principles simulations. Then, starting from the static Bethe-Salpeter equation (BSE) – which is the state-of-the-art tool to compute excitons – I will present the theoretical approach to obtain spectroscopic observables including a microscopic description of exciton-phonon interactions, with a particular focus on the role of electronic screening. I will then discuss the computational implementation of a workflow for efficient exciton-phonon calculations – as recently implemented in the Yambo code – obtained by exploiting symmetry operations on exciton wavefunctions and electron-phonon matrix elements in momentum space. Finally, I will illustrate applications of this methodology for the characterization of relevant layered and 2D materials, including phonon-assisted satellites appearing in the luminescence spectra of boron nitride, as well as scattering amplitudes and Raman spectra in monolayer transition metal dichalcogenides.

This talk is part of the Theory of Condensed Matter series.

This talk is included in these lists:

• All Cavendish Laboratory Seminars
• All Talks (aka the CURE list)
• Centre for Health Leadership and Enterprise
• Combined TCM Seminars and TCM blackboard seminar listing
• Featured lists
• Lennard-Jones Centre external
• ME Seminar
• Neurons, Fake News, DNA and your iPhone: The Mathematics of Information
• PMRFPS's
• School of Physical Sciences
• Seminar Room 3, RDC
• Theory of Condensed Matter
• Thin Film Magnetic Talks
• few29

Note that ex-directory lists are not shown.