Dresden 2020 – wissenschaftliches Programm

Die DPG-Frühjahrstagung in Dresden musste abgesagt werden! Lesen Sie mehr ...

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

TT: Fachverband Tiefe Temperaturen

TT 34: Correlated Electrons: f-Electron Systems and Heavy Fermions 1

TT 34.11: Vortrag

Mittwoch, 18. März 2020, 12:15–12:30, HSZ 204

Crystal growth and characterization of isotope-pure YbRh₂Si₂ (¹⁷¹Yb, ¹⁷³Yb, ¹⁷⁴Yb) — •Sebastian Witt¹, Susanna Rongstock¹, Thanh Duc Nguyen¹, Manuel Brando², and Cornelius Krellner¹ — ¹Physikalisches Institut, Goethe University, Frankfurt, Germany — ²Max-Planck-Institute for Chemical Physics of Solids, Dresden, Germany

A central question in condensed matter research concerns the interplay between quantum criticality and unconventional superconductivity in strongly correlated electron systems such as heavy-electron systems. Recently, superconductivity was also discovered in the quantum-critical material YbRh₂Si₂ at 2mK [1]. So far the interplay between electronic and nuclear moments of Yb and its impact on the superconductivity is not settled. For that reason, it is essential to investigate YbRh₂Si₂ samples with a well-defined Yb nuclear spin.

In this talk, we report the crystal growth with the entire range of nuclear spin number in the single crystals (¹⁷¹Yb: I = 1/2, ¹⁷³Yb: I = 5/2, ¹⁷⁴Yb: I = 0). For the crystal growth we developed a new setup for small masses, especially for the metallothermic reduction of metallic Yb from Yb₂O₃. Besides the single crystal characterization (Laue, PXRD) we will present measurements of the resistivity and isotopic composition. To investigate the influence of nuclear spin on the electronic degrees of freedom, we will show the heat capacity around the antiferromagnetic transition at 70mK.

[1] E. Schuberth et al., Science, 351, 485-488 (2016).