Parts | Days | Selection | Search | Updates | Downloads | Help
TT: Fachverband Tiefe Temperaturen
TT 11: Heavy Fermions
TT 11.5: Talk
Monday, March 18, 2024, 16:00–16:15, H 3005
Characteristic energy scales in CeRh2As2 — •O. Stockert1, M. M. Koza2, and S. Khim1 — 1Max-Planck-Institut für Chemische Physik fester Stoffe, Dresden, Germany — 2Institut Laue-Langevin, Grenoble, France
The heavy-fermion superconductor CeRh2As2 is located close to a quantum critical point and attracts a lot of attention due to its interplay of unconventional heavy-fermion superconductivity with Tc ≈ 0.25 K and a possibly quadrupolar ordered state setting in above Tc. Recent measurements suggest the existence of antiferromagnetic order above the superconducting transition temperature. To better understand the unusual low-temperature properties of CeRh2As2, a knowledge of the relevant characteristic energy scales is important. We performed inelastic neutron scattering on CeRh2As2 powder to study the crystalline-electric-field (CEF) excitations and to look for the Kondo fluctuations. Our experiments reveal a low-lying excited CEF above the ground state doublet in addition to a Kondo enery scale of around 30 K. We will discuss our results in comparison to the previously suggested quadrupolar ground state and their implications for the ordered state.
Keywords: heavy-fermion superconductor; crystalline-electric-field excitations; Kondo effect; quadrupolar order