Contact: 李源 研究员

Abstract:

Uniaxial strain is an increasingly important tuning parameter in the physics of quantum materials, and in the past decade it has been used to study and manipulate both electronic and structural ordering phenomena in a wide range of systems. Yet uniaxial strain studies of dynamical properties such as lattice vibrations and spin excitations are still in their infancy, since it is difficult to obtain controlled uniaxial strain in large bulk samples suitable for use with techniques such as inelastic neutron scattering. In this talk, I will present new advances that have been made possible by the development of high-force uniaxial strain cells, which use helium gas pneumatics to generate large and finely controllable stress levels. These devices have enabled a number of important insights using both in situ and ex situ uniaxial deformation, and I will discuss our recent results on the effects of elastic and plastic deformation on phonons in the incipient ferroelectrics SrTiO₃ and KTaO₃ [1-3] and PbTe, the manipulation of structural fluctuations in the cuprate high-temperature superconductor La_2-xSr_xCuO₄ [4], and strain tuning of magnetism in the Kitaev spin liquid candidate material RuCl₃.

[1] S. Hameed et al., Nat. Mater. 21, 54 (2022)
[2] I. Khayr et al., Phys. Rev. Mater. 8, 124404 (2024)
[3] I. Khayr et al., arXiv:2511.10623 (2025)
[4] R. J. Spieker et al., Phys. Rev. B 113, 014101 (2026)

About the speaker:

Dr. Damjan Pelc obtained his PhD from the University of Zagreb, Croatia, in 2017, and spent three years as a postdoctoral researcher at the University of Minnesota in the group of Prof. Martin Greven. He is now Associate Professor at the University of Zagreb, where he leads a group with focus on experimental condensed matter physics. His interests are in the field of quantum materials, primarily unconventional superconductivity in complex oxides and layered materials, as well as exotic magnetism and quantum spin liquid phases. His group uses a combination of experimental approaches, including neutron and x-ray scattering, optical spectroscopy, and magnetic resonance, and is actively engaged in the development of new techniques.