Regensburg 2022 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
TT: Fachverband Tiefe Temperaturen
TT 24: Quantum-Critical Phenomena
TT 24.4: Vortrag
Mittwoch, 7. September 2022, 15:45–16:00, H23
Specific heat and magnetocaloric effect at transverse-field quantum criticality in LiHoF4 — •Andreas Wendl1, Heike Eisenlohr2, Jan Spallek1, Christopher Duvinage1, Matthias Vojta2, and Christian Pfleiderer1,3,4 — 1Physik Department, TU München, Garching, Germany — 2Institut für Theoretische Physik and Würzburg-Dresden Cluster of Excellence ct.qmat, TU Dresden, Dresden, Germany — 3Centre for QuantumEngineering (ZQE), TU München, Garching, Germany — 4Munich Centre for Quantum Science and Technology (MCQST), TU München, Garching, Germany
The perhaps best understood example of a quantum critical point is the response of the dipolar Ising ferromagnet LiHoF4 under a transverse field [1-3]. We report an experimental and theoretical study of the specific heat and magneto-caloric effect of LiHoF4 as a function magnetic field down to mK temperatures using a bespoke experimental set-up permitting studies under arbitrary magnetic field orientations. We derive the low temperature entropy landscape and discuss our findings in terms of a theoretical model taking quantitatively into account the non-Kramers nature of the Ho ions, the effects of hyperfine coupling and the presence of magnetic domains.
[1] D. Bitko et al., Phys. Rev. Lett. 77, 940 (1996)
[2] H. M. Ronnow et al., Science 308, 389 (2005)
[3] P. B. Chakraborty et al., Phys. Rev. B 70, 144411 (2004).