Upcoming Event: Babuška Forum

Towards the predictive computational modeling of quantum materials at finite temperatures

Antonios Alvertis,

Abstract

Understanding the microscopic properties of quantum materials is critical towards designing novel energy technologies. Decades of research has resulted in increasingly accurate ways of modeling electron-electron interactions, as well as the interactions between electrons and positively charged holes, which underlie several of the application-relevant properties of quantum materials. However, a factor which is often disregarded in describing such electronic properties is atomic motion, which is present not only at finite temperatures, but even at absolute zero.

In this talk, I will present different theoretical methods that I have developed in order to account for the effects of atomic motion on electronic interactions, and I will show examples of how atomic motion can radically alter the physics of diverse quantum materials. Specifically, I will show that temperature can reduce the binding energy of optically excited states by 70% in diverse semiconductors and insulators [1], and that interlayer atomic motion can greatly renormalize the excited state properties of 2D heterostructures [2]. I will demonstrate that zero-point motion substantially modifies the electronic wave function of molecular crystals, revealing a pathway towards rapid energy transfer in photovoltaics [3], and how this allowed me to minimize heat losses in organic crystals, achieving some of the world’s most efficient LEDs [4].

While these insights have been made possible through the systematic implementation of my methods on high-performance computers, it is becoming increasingly clear that for so-called strongly-correlated materials, where electrons interact strongly, the exponential scaling of resources that is imposed by quantum mechanics makes their quantitative first-principles modeling a challenge. I will show that emerging quantum computers could hold great promise in circumventing this problem [5,6], and introduce a practical way of accounting for the effects of atomic motion when modeling quantum materials on such hardware, without increasing the required resources [6]. This has enabled me to propose the first ever fully first-principles explanation of the formation of Cooper pairs in certain semiconductors such as SrTiO3, which has remained obscured since the discovery of superconductivity in these systems in 1964. 

[1] Alvertis, Neaton et al. Proceedings of the National Academy of Sciences 121, e2403434121 (2024)
[2] Lee, Alvertis, Li, Louie, Filip Neaton, Kioupakis. Physical Review Letters 133, 206901 (2024)
[3] Alvertis, Haber, Neaton et al. Physical Review Letters 130, 086401 (2023)
[4] Ghosh, Alvertis, Friend, Rao et al. Nature 629, 355 (2024)
[5] Alvertis, Khan, Tubman. Physical Review Applied 23, 044028 (2025)
[6] Alvertis, Khan, Iadecola, Orth, Tubman. Quantum 9, 1748 (2025)
[7] Tubman, Coveney, Hsu, Montoya-Castillo, Filip, Neaton, Li, Vlcek, Alvertis, arXiv: 2501.17230 (2025)"

Biography

Antonios Alvertis is an incoming assistant professor at the Oden Institute and the Department of Physics at UT Austin, with an interest in combining high-performance computing and quantum computing technologies, in order to understand the properties of complex quantum materials. He moved to the USA in 2021, on a joint postdoctoral research fellowship from the Cambridge University and UC Berkeley Physics departments, and then stayed on as a postdoc at Lawrence Berkeley National Lab until August of 2023.

During this time, he developed theoretical methods and software packages for accurately describing the excited state properties of diverse solids, and accounting for the effects of temperature on their physics. For this work he received the Theoretical Physics award of the Academy of Athens in December of 2024, and was one of five finalists for the international ‘Volker Heine’ research award in August of 2025. From 2023 to 2025, he was a research scientist at the NASA Ames research center, where he deepened his expertise on quantum computing and its application to materials-related application.

He received his Ph.D. in Physics from the University of Cambridge in 2021, where his thesis was awarded the Cavendish Ph.D. prize and the Springer Thesis award, recognizing the contributions of his theoretical work in elucidating the complex photophysics of organic chromophores.