arXiv subjects

Lucy Whalley

Publications and source records attributed to Lucy Whalley.

3 recordsLinked to original sources

arXiv2026

Singing Materials: Initial experiments in applying sonification to phonon spectra

Solid materials may appear static, but at the atomic scale they are in constant vibrational motion. These vibrations, described by phonons, govern many key material properties, including structural stability, mechanical strength, optical behaviour, and thermal transport. Understanding phonon physics is therefore central to the rational design of materials with targeted functionalities. Singing Materials is a research project that explores how sonification can be applied to this domain. In this work, we introduce `SingingMaterials`, a modular Python package for sonifying materials simulation data. The software interfaces with the Materials Project database and is designed to be extensible, enabling the incorporation of additional sonification strategies and data sources. Built using the Sonification Toolkit `STRAUSS`, the current implementation supports three core approaches: spectral, synthesised, and sample-based. We demonstrate these approaches using phonon density-of-states data and evaluate their effectiveness through a user study, investigating whether listeners can distinguish differences in material properties from their auditory representations. The results show that sonification can provide an interpretable and complementary approach for exploring vibrational materials data.

cond-mat.mtrl-sci↗

arXiv2026

Anion Ordering and Phase Stability Govern Optical Band Gaps in BaZr(S,Se)3

Chalcogenide perovskites have emerged as promising lead free materials for photovoltaic and thermoelectric applications. Among them, BaZrS3 has attracted particular attention due to its thermal and chemical stability, favorable optoelectronic properties, and low thermal conductivity. Here, we combine molecular dynamics and Monte Carlo simulations based on machine learned interatomic potentials with scanning transmission electron microscopy to investigate mixing thermodynamics and phase stability in the BaZr(S,Se)3 system. We identify an unusual ordered structure that persists at room temperature, most prominently at 33% S, where S and Se atoms form alternating layers within the crystal. Free energy calculations yield the temperature composition phase diagram, including a nonperovskite delta phase in the Se rich limit and a perovskite phase in the S rich limit, separated by a broad two phase region. Analysis of the dielectric function and the absorption coefficient demonstrates that composition, crystal structure, and anion ordering jointly control the optical band gap. Selenium alloying enables tuning between approximately 1.6 and 1.9eV, while anion ordering within a given composition reduces the gap by about 0.12eV. Lastly, variations between structural polymorphs give rise to band gap differences of up to 0.4eV.

cond-mat.mtrl-sci↗

arXiv2026

Diverse polymorphism in Ruddlesden-Popper chalcogenides

Ruddlesden-Popper (RP) chalcogenides are stable, non-toxic candidates for optoelectronic or thermoelectric applications. The structural diversity of RP oxides is already exploited to tune properties or achieve more advanced functionalities like multiferroicity, however, little is known about the structural evolution of RP chalcogenides. In this work, we develop a high-accuracy machine-learned interatomic potential to run large-scale molecular dynamics simulations on $Ba_{n+1}Zr_nS_{3n+1}$ for $n=1$ to $n=6$. We predict new polymorphs for each $n$-value, calculate their corresponding phase transition temperatures, and validate our approach through comparison to published experimental results. We find that the $n=1$ phase exhibits negative thermal expansion, that $n=1$ and $n=3$ undergo unusual ascending symmetry breaking, and that phases with $n\geq4$ form layer-dependent tilt patterns previously unreported for inorganic RP materials. This unique behaviour results from competition between octahedral rotations and rumpling at the rocksalt interface, and suggests new strategies for accessing advanced functionalities.

cond-mat.mtrl-sci↗