Andrej Pustogow
Tuning materials properties on demand is at the heart of condensed matter science. Magnetism and charge transport are strongly linked to the overlap of electronic wave functions and can be, thus, manipulated by varying the electronic bandwidth through chemical substitution or physical pressure. Yet, a controlled modification of geometrical frustration of transfer integrals and exchange interactions remained inaccessible so far. Here, we utilize the recent advancements in strain tuning of unconventional superconductors [1-3] and apply uniaxial stress to a clean kagome-lattice system without disorder [4]. As we break the hexagonal symmetry in a continuous manner, we achieve in situ tuning of antiferromagnetic order within one single crystal through a controlled release of frustration strength [4]. We further apply uniaxial strain to finetune a metal-insulator transition with unprecedented precision in a frustrated Mott insulator [5]. Our pioneering endeavors [4,5] demonstrate uniaxial strain as a powerful tool to tweak interacting electrons on frustrated lattices – with the potential of tuning frustration-induced topological flat-band systems
[6,7], that may be applied in near future to generate ‘green’ energy in metallic thermoelectrics [8].
[1] C.W. Hicks et al., Science 344, 283 LP (2014)
[2] A. Pustogow et al., Nature 574, 72–75 (2019)
[3] A. Chronister et al., npj Quantum Mater. 7, 113 (2022)
[4] Jierong Wang, Y.-S. Su, M. Spitaler, K.M. Zoch, C. Krellner, P. Puphal, S.E. Brown, and A. Pustogow,
Phys. Rev. Lett. 131, 256501 (2023)
[5] A. Pustogow, Y. Kawasugi, H. Sakurakoji, N. Tajima, Nat. Commun. 14, 1960 (2023)
[6] L. Ye et al., Nat. Phys. 20, 610 (2024)
[7] H. J. Kim, M. J. Kim, J. Lee, J. M. Ok, and C.
-J. Kang, Phys. Rev. B 110, 024504 (2024)
[8] F. Garmroudi, I. Serhiienko, S. Di Cataldo, M. Parzer, A. Riss, M. Grasser, S. Stockinger, S.
Khmelevskyi, K. Pryga, B. Wiendlocha, K. Held, T. Mori, E. Bauer, and A. Pustogow, arXiv:2404.08067