BİLKENT UNIVERSITY, DEPARTMENT of PHYSICS
Burak Güzeltürk
Argonne National Laboratory
“Light-Driven Control of Quantum Materials”
Abstract
Many of the most intriguing properties of quantum materials, including ferroicity, correlated electronic order, and adaptive functionality, emerge from a delicate interplay between charge, lattice, spin, and orbitals. Under equilibrium conditions, these competing interactions often constrain materials to a limited set of accessible phases. A central frontier in condensed matter physics is whether nonequilibrium excitation can instead access and control material states that are difficult or impossible to reach through conventional thermodynamic pathways. In this talk, I will discuss our efforts to uncover and manipulate such light-driven states using ultrafast structural probes. I will first show how pulsed optical excitation can transiently reconfigure the nanoscale ferroelectric domain network in multiferroic BiFeO₃ [1], revealing how photoinduced strain and intrinsic spatial heterogeneity govern domain evolution. I will then show how photoexcitation can drive a transient structural symmetry transformation in PbS quantum dots [2], demonstrating optical control of symmetry in a quantum-confined material. I will also discuss emerging examples in metal-halide perovskites where photoexcitation produces much longer-lived structural responses and metastable-like states. Together, these results illustrate how following atomic and mesoscale structural pathways across multiple time and length scales can provide new routes toward controlling nonequilibrium functionality in quantum materials.
[1] B. Guzelturk et al., Advanced Materials 35, 2306029 (2023).
[2] B. Guzelturk et al., Advanced Materials 37, 2414196 (2025).
Burak Güzeltürk is a physicist in the X-ray Science Division at Argonne National Laboratory. Before joining Argonne, he was a postdoctoral scholar in Materials Science and Engineering at Stanford University and SLAC National Accelerator Laboratory. He received his B.Sc., M.Sc., and Ph.D. degrees in Electrical and Electronics Engineering from Bilkent University. His research focuses on understanding how ultrafast energy flow reshapes the atomic and electronic structure of quantum and functional materials, and how these pathways can be harnessed to create and control nonequilibrium material properties. His work combines time-resolved X-ray and electron scattering with transient optical and terahertz spectroscopy to reveal coupled dynamics across atomic, nanoscale, and mesoscale length scales. His research has been recently recognized by the ACS Nano Lectureship Award.
Date: 30 September 2026, Wednesday
Time: 15:30
Place: SA-240
All interested are cordially invited.