Ferromagnetic Quantum Critical Endpoint in UCoAl
作者： Dai Aoki , Tristan Combier , Valentin Taufour , Tatsuma D. Matsuda , Georg Knebel
关键词: Materials science 、 Condensed matter physics 、 Paramagnetism 、 Ground state 、 Magnetostriction 、 Ferromagnetic superconductor 、 Ferromagnetism 、 Electrical resistivity and conductivity 、 Effective mass (solid-state physics) 、 Ambient pressure
摘要: Resistivity and magnetostriction measurements were performed at high magnetic fields under pressure on UCoAl. At ambient pressure, the 1st order metamagnetic transition H_m ~ 0.7 T from paramagnetic ground state to field-induced ferromagnetic changes a crossover finite temperature T_0 ~11 K. With increasing linearly increases, while decreases is suppressed quantum critical endpoint (QCEP, P_QCEP 1.5 GPa, 7 T). higher value of identified as continuously new anomaly appears above field H* in resistivity measurements. The dependence effective mass (m*) obtained by specific heat exhibits step-like drop pressure. it gradually into peak structure sharp enhancement m* observed near QCEP. Above P_QCEP, reduced, broad plateau found between H*. We compare our results UCoAl with those superconductor UGe2 itinerant ruthenate Sr3Ru2O7.
arxiv.org
ipap.jp参考文章(58)
R. A. Fisher, C. Marcenat, N. E. Phillips, P. Haen, F. Lapierre, P. Lejay, J. Flouquet, J. Voiron, The magnetic instability in the heavy fermion compounds Ce 1−x La x Ru 2 Si 2 Journal of Low Temperature Physics. ,vol. 84, pp. 49- 86 ,(1991) , 10.1007/BF00681617
W. Wu, A. McCollam, S. A. Grigera, R. S. Perry, A. P. Mackenzie, S. R. Julian, Quantum critical metamagnetism of Sr3Ru2O7 under hydrostatic pressure Physical Review B. ,vol. 83, pp. 1- 7 ,(2011) , 10.1103/PHYSREVB.83.045106
Y. Ihara, T. Hattori, K. Ishida, Y. Nakai, E. Osaki, K. Deguchi, N. K. Sato, I. Satoh, Anisotropic Magnetic Fluctuations in the Ferromagnetic Superconductor UCoGe Studied by Direction-Dependent ^{59}Co NMR Measurements Physical Review Letters. ,vol. 105, pp. 206403- ,(2010) , 10.1103/PHYSREVLETT.105.206403
Shinji Watanabe, Kazumasa Miyake, Atsushi Tsuruta, Jacques Flouquet, Valence Fluctuations Revealed by Magnetic Field Scan: Comparison with Experiments in YbXCu_4 (X=In, Ag, Cd) and CeYIn_5 (Y=Ir, Rh) arXiv: Strongly Correlated Electrons. ,(2009) , 10.1143/JPSJ.78.104706
M. Uhlarz, C. Pfleiderer, S. M. Hayden, Quantum phase transitions in the itinerant ferromagnet ZrZn2. Physical Review Letters. ,vol. 93, pp. 256404- 256600 ,(2004) , 10.1103/PHYSREVLETT.93.256404
Dai Aoki, Tatsuma D. Matsuda, Frédéric Hardy, Christoph Meingast, Valentin Taufour, Elena Hassinger, Ilya Sheikin, Carley Paulsen, Georg Knebel, Hisashi Kotegawa, Jacques Flouquet, Superconductivity Reinforced by Magnetic Field and the Magnetic Instability in Uranium Ferromagnets Journal of the Physical Society of Japan. ,vol. 80, ,(2011) , 10.1143/JPSJS.80SA.SA008
F Lévy, I Sheikin, A Huxley, None, Acute enhancement of the upper critical field for superconductivity approaching a quantum critical point in URhGe Nature Physics. ,vol. 3, pp. 460- 463 ,(2007) , 10.1038/NPHYS608
A. B. Shick, W. E. Pickett, Magnetism, Spin-Orbit Coupling, and Superconducting Pairing in UGe 2 Physical Review Letters. ,vol. 86, pp. 300- 303 ,(2001) , 10.1103/PHYSREVLETT.86.300
Masugu Sato, Yoshihiro Koike, Susumu Katano, Naoto Metoki, Hiroaki Kadowaki, Shuzo Kawarazaki, Field-induced Ferromagnetic Correlation in the Metamagnetic Crossover in CeRu2Si2as Studied by Neutron Scattering Journal of the Physical Society of Japan. ,vol. 73, pp. 3418- 3421 ,(2004) , 10.1143/JPSJ.73.3418
M Shimizu, On the conditions of ferromagnetism by the band model Proceedings of the Physical Society. ,vol. 84, pp. 397- 408 ,(1964) , 10.1088/0370-1328/84/3/309