ÖPG–CMD Joint Meeting 2026 in Graz

Next week condensed matter physics comes to our doorstep. From 20 to 25 September 2026, the University of Graz and the Graz University of Technology jointly host the ÖPG–CMD Joint Meeting 2026 — the 75th Annual Meeting of the Austrian Physical Society together with the 32nd Meeting of the Condensed Matter Division of the European Physical Society. The CMD section alone spans 42 mini-colloquia and thirteen plenary talks, and it runs alongside the full ÖPG program, all of it at the site of the future Graz Center of Physics, and a few minutes from our institute.

Having the CMD meeting in Graz is a rare piece of luck, and our group is making the most of it. Below is where to find us.

M24 — Computational Frontiers in Structure Prediction, Lattice Dynamics, and Electron-Phonon Coupling

Together with Lilia Boeri (Sapienza University of Rome), I organized the mini-colloquium M24, which brings together the three ingredients that any modern first-principles prediction of a superconductor needs: getting the structure right, getting the lattice dynamics right, and getting the coupling between electrons and phonons right. The three are not independent — anharmonicity and disorder feed back into all of them — and the session is built around groups that are pushing on that entanglement rather than treating the steps in isolation.

M24 – Session 1: Thursday 24 September, 16:00–18:00, HS 12.11 (chair: Christoph Heil)

It opens with an invited talk by Simone Di Cataldo on what first-principles calculations can already say about structural disorder and superconductivity, followed by Eva’s invited talk (below). The contributed talks cover ternary hydride searches with hot-AIRSS, spin–phonon coupling in NV diamond, machine-learning-based non-adiabatic molecular dynamics, and pressure-enhanced heat transport in organic semiconductors. The M24 poster session runs as part of PS2 (Wed 23 – Fri 25).

Wednesday 23 — Luka Wibmer, contributed talk

Application of the GQCA method to the composition-driven Mott transition in titanate/vanadate alloys
Wednesday 23 September, 16:30–16:45, HS 15.13 (COND – Session 2, ÖPG section)

SrTiO₃ is a band insulator, SrVO₃ a moderately correlated metal, and the solid solution between them tunes continuously from one to the other — except that reported critical concentrations scatter across x_c ≈ 0.4–0.7 and the mechanism sits awkwardly between Mott physics and Anderson localization. Part of the trouble is that a thermally disordered alloy is not any single supercell but an ensemble of many, and committing to one quietly discards that physics. Luka will show what the generalized quasichemical approximation does here, treating every quantity as a thermodynamically weighted ensemble average over symmetry-inequivalent clusters. Details in our recent preprint.

Thursday 24, morning — Christoph Heil, invited talk

The case for phonon-mediated superconductivity in Sr₂RuO₄
Thursday 24 September, 10:30–12:30, HS 15.14 (M06 – Session 3: Interaction Effects in Correlated Systems with Higher-Order Van Hove Singularities and Flat Bands)

Sr₂RuO₄ has been the standard-bearer for unconventional, non-phonon pairing for three decades. Its structural similarity to the cuprates and an early, now disproven consensus on odd-parity pairing entrenched the assumption that the pairing is governed by spin fluctuations, leaving the role of phonons largely unexplored. In this talk I revisit that assumption from first principles. Our results establish the electron-phonon interaction as a key ingredient of the superconductivity in Sr₂RuO₄. A quantitative description will nevertheless require treating it on equal footing with electronic correlations and spin fluctuations.

Thursday 24, afternoon — Eva Kogler, invited talk

Toward a predictive ab initio description of superconductivity in NbN
Thursday 24 September, 16:00–18:00, HS 12.11 (M24 – Session 1)

NbN is the workhorse of superconducting device technology and, at the same time, a textbook case of why ab initio superconductivity is hard: the rocksalt phase is dynamically unstable at the harmonic level, its properties depend sensitively on nitrogen vacancies, and the electron-phonon coupling is strong. Eva will lay out how far a genuinely predictive description can be pushed, building on our recent work showing that quantum anharmonicity stabilizes the vacancy-free cubic phase — see Vacancy-free cubic superconducting NbN enabled by quantum anharmonicity in Communications Materials, and our post about it.

Friday 25 — Dominik Spath, contributed talk

Ultrafast dynamics and light-induced superconductivity from first principles
Friday 25 September, 10:30–12:30, HS 15.05 (M15 – Session 2: Light-Wave Driven Dynamics in Quantum Materials)

Light-induced superconductivity has produced a decade of striking experiments and remarkably few parameter-free calculations. Dominik will present the first-principles framework we have been developing with our collaborators at MIT for the non-equilibrium dynamics of conventional superconductors — the machinery needed to ask whether a given drive in a given material actually enhances pairing, rather than fitting the answer after the fact. Background in our preprint announcement.

Posters — Ralf Meyer

Universal MLIPs for High-Throughput Anharmonic Stability Screening (P051)
Poster session PS2, Wednesday 23 – Friday 25 (M24)

Ralf will be showing how far universal machine-learned interatomic potentials can be pushed as a pre-filter for anharmonic stability, which is exactly the bottleneck that keeps high-throughput searches for new superconductors expensive.

If you are coming to Graz, please do come to the talks and the M24 session — and find any of us in the coffee breaks. We are always happy to talk about superconductivity, anharmonicity, disorder, or why your favourite material should be the next one we compute.