SKM 2023 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

TT: Fachverband Tiefe Temperaturen

TT 47: Quantum-Critical Phenomena

TT 47.2: Vortrag

Donnerstag, 30. März 2023, 09:45–10:00, HSZ 204

Phonon softening close to a structural instability at zero temperature — T. Gruner^1,2, S. Lucas¹, C. Geibel¹, K. Kaneko³, S. Tsutsui^4,5, K. Schmalzl⁶, and •O. Stockert¹ — ¹Max-Planck-Institut für Chemische Physik fester Stoffe, 01187 Dresden, Germany — ²Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom — ³Materials Sciences Research Center, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195, Japan — ⁴Japan Synchrotron Radiation Research Institute, SPring-8, Sayo, Hyogo 679-5198, Japan — ⁵Institute of Quantum Beam Science, Graduate School of Science and Engineering, Ibaraki University, Hitachi, Ibaraki 316-8511, Japan — ⁶Jülich Centre for Neutron Science JCNS, Forschungszentrum Jülich GmbH, Outstation at ILL, 38042 Grenoble, France

The structural transition in LuPt₂In is interesting since it can be tuned to zero temperature upon substituting Pd for Pt in Lu(Pt_1−xPd_x)₂In. Of particular interest is the appearance of a superconducting dome around the structural quantum criticality. We combined inelastic neutron and x-ray scattering measurements and studied in detail this structural transition in Lu(Pt_1−xPd_x)₂In. As a result we determined the low-energy phonon dispersions and clearly identified the relevant phonon branch becoming soft at the transition. In general, the theoretical calculations broadly agree with the measured dispersion. However, large tails of the superstructure intensity above the structural transition clearly point to a non-mean-field behavior, which might be related to quantum criticality and/or the superconducting dome.