Seminarium Oddziału Badań Magnetyków
Microsoft Teams
The mystery of CeRhIn5 in high magnetic field
dr hab. Ilya Sheikin
Narodowe Laboratorium Silnych Pól Magnetycznych (LNCMI) w Grenoble we Francji
Seminarium odbędzie się zdalnie w aplikacji Microsoft Teams. W celu wzięcia udziału w wydarzeniu należy dołączyć do zespołu Seminarium OBM.Można do niego dołączyć na stałe przy użyciu kodu dostępu ol7omod (dotyczy to osób posiadających konto w domenie intibs.pl, pozostałe osoby proszę o kontakt z dr. hab. Adamem Pikulem ()).
Streszczenie:
Antiferromagnetic CeRhIn5, discovered some two decades ago, is now one of the best-studied Ce-based heavy-fermion compounds. Yet, it continues to attract a lot of attention of the scientific community due to its unique behaviour in high magnetic fields. When the magnetic field is applied along, or close to, the c axis, a new phase characterized by a pronounced in-plane electronic anisotropy emerges at B* ≈ 30 T, well below the critical field, Bc ≈ 50 T, to suppress the antiferromagnetic order. The exact origin of this new phase, originally suggested to be either a density-wave phase [1] or an electronic-nematic state [2], remains elusive. It was further suggested that a field-induced Fermi-surface reconstruction corresponding to the delocalization of the f electrons occurs at B* [3].
In my talk, I will present our recent results of the high-field de Haas-van Alphen (dHvA) effect, specific-heat, and ultrasound-velocity measurements in CeRhIn5. Our comprehensive dHvA measurements in fields up to 70 T unambiguously suggest that the Ce 4f electrons in CeRhIn5 remain localized over the whole field range. This rules out any Fermi-surface reconstruction, either at the suggested nematic phase transition at B∗ ≈ 30 T or at the putative quantum critical point at Bc ≈ 50 T [4]. Our specific-heat measurements in fields applied along the c axis revealed a small but distinct anomaly at B∗, which we discuss in terms of a field-induced transition, probably weakly first-order. We further suggest that the transition corresponds to a change of magnetic structure [5]. This hypothesis is supported by our ultrasound velocity measurements performed in magnetic fields slightly tilted from the c axis [6].
1. P. J. W. Moll et al., Nat. Commun. 6, 6663 (2015).
2. F. Ronning et al., Nature 548, 313 (2017).
3. L. Jiao et al., Proc. Natl. Acad. Sci. USA 112, 673 (2015).
4. S. Mishra et al., Phys. Rev. Lett. 126, 016403 (2021).
5. S. Mishra et al., Phys. Rev. B 103, 045110 (2021).
6. S. Mishra et al., to be submitted to Phys. Rev. Lett.
