Alejandro Silhanek

Nonlocal magnetic field-tuned quantum criticality in cubic CeIn3-xSnx (x=0.25)

We show that antiferromagnetism in lightly (approximately 8%) Sn-doped CeIn3 terminates at a critical field mu0H(c) = 42 +/- 2 T. Electrical transport and thermodynamic measurements reveal the effective mass m* not to diverge, suggesting that cubic CeIn3 is representative of a critical spin-density wave (SDW) scenario, unlike the local quantum critical points reported in anisotropic systems such as CeCu(6-x)Au(x) and YbRh2Si(2-x)Ge(x). The existence of a maximum in m* at a lower field mu0H(x) = 30 +/- 1 T may be interpreted as a field-induced crossover from local moment to SDW behavior as the Néel temperature falls below the Fermi temperature.

Irreversible dynamics of the phase boundary in U(Ru0.96Rh0.04)2Si2 and implications for ordering

We report measurements and analysis of the specific heat and magnetocaloric effect-induced temperature changes at the phase boundary into the single magnetic field-induced phase (phase II) of U(Ru0.96Rh0.04)2Si2, which yield irreversible properties similar to those at the valence transition of Yb(1-x)Y(x)InCu4. To explain these similarities, we propose a bootstrap mechanism by which lattice parameter changes caused by an electric quadrupolar order parameter within phase II become coupled to the 5f-electron hybridization, giving rise to a valence change at the transition.

Quantum Critical 5f Electrons Avoid Singularities in U(Ru, Rh)2Si2

We present specific heat measurements of 4% Rh-doped URu2Si2 at magnetic fields around the proposed metamagnetic transition field H(m) approximately 34 T, revealing striking similarities to the isotructural Ce analog CeRu2Si2 for H>H(m). This suggests that strongly renormalized hybridized-band models apply equally well to both systems. The vanishing bandwidths as H-->H(m) are consistent with a quantum-critical point close to H(m). The existence of a phase transition into an ordered phase in the vicinity of H(m) for 4% Rh-doped URu2Si2, but not for CeRu2Si2, is consistent with a stronger superexchange in the case of the U 5f system. Irreversible processes at the transition indicate a strong coupling of the 5f orbitals to the lattice, most suggestive of electric quadrupolar order.

Suppression of antiferromagnetic ordering by magnetic field in Ce0.6La0.4In3

Electrical resistivity and specifc heat measurements were performed at high magnetic fields up to 45 T in Ce0.6La0.4In3, which is the La-substituted material to heavy fermion antiferromagnet CeIn3. In Ce0.6La0.4In3, the H-T phase diagram was drawn and the critical magnetic field was estimated to be approximately at 39 T. The critical field of Ce0.6La0.4In3 is about 20 T lower than that at 60 T of CeIn3. Lower critical field facilitates observing Fermi surfaces when crossing phase boundary between antiferromagnetic and paramagnetic phases. Thus, the phase diagram obtained from our results should be a guide when we compare the Fermi surface topology in antiferromagnetic phase to that in paramagnetic phase.

Physical properties at high magnetic fields in CeIn2.75Sn0.25CeIn2.75Sn0.25

High magnetic field induces quantum criticality in CeIn3CeIn3 with suppressing the Neel temperature. Estimated quantum critical field of CeIn3CeIn3 is about 60xa0T where the Neel temperature is suppressed to reach absolute zero. The magnetic field (60xa0T) is too high to measure electrical resistivity or specific heat precisely. Sn doping to In site of CeIn3CeIn3 reduces the Neel temperature. Reduction of Neel temperature indicates lower critical field to facilitate investigation of electronic states at high magnetic fields. Electrical resistivity and specific heat in CeIn2.85Sn0.25CeIn2.85Sn0.25 were measured to map an H–T phase diagram.

Physical properties at high magnetic fields in CeIn2.75Sn0.25

High magnetic field induces quantum criticality in CeIn3CeIn3 with suppressing the Neel temperature. Estimated quantum critical field of CeIn3CeIn3 is about 60xa0T where the Neel temperature is suppressed to reach absolute zero. The magnetic field (60xa0T) is too high to measure electrical resistivity or specific heat precisely. Sn doping to In site of CeIn3CeIn3 reduces the Neel temperature. Reduction of Neel temperature indicates lower critical field to facilitate investigation of electronic states at high magnetic fields. Electrical resistivity and specific heat in CeIn2.85Sn0.25CeIn2.85Sn0.25 were measured to map an H–T phase diagram.

Physical properties at high magnetic fields in

High magnetic field induces quantum criticality in CeIn3CeIn3 with suppressing the Neel temperature. Estimated quantum critical field of CeIn3CeIn3 is about 60xa0T where the Neel temperature is suppressed to reach absolute zero. The magnetic field (60xa0T) is too high to measure electrical resistivity or specific heat precisely. Sn doping to In site of CeIn3CeIn3 reduces the Neel temperature. Reduction of Neel temperature indicates lower critical field to facilitate investigation of electronic states at high magnetic fields. Electrical resistivity and specific heat in CeIn2.85Sn0.25CeIn2.85Sn0.25 were measured to map an H–T phase diagram.