Related papers: Quantum critical 5f-electrons avoid singularities …
With understood exceptions, conventional superconductivity does not coexist with long-range magnetic order[1]. In contrast, unconventional superconductivity develops near a boundary separating magnetically ordered and magnetically…
We report on detailed ac calorimetry measurements under high pressure and magnetic field of CeRhIn5. Under hydrostatic pressure the antiferromagnetic order vanishes near p_c*=2 GPa due to a first order transition. Superconductivity is found…
We performed ultrasonic and temperature measurements under pulsed magnetic fields on CeIrIn$_5$ to investigate whether or not the origin of metamagnetic transition and field-induced Lifshitz transition was described by the anisotropic…
The electrical resistivity rho(T) of single crystalline CeCu_5Au under pressure was measured in the temperature range 30mK<T<300K. Pressure suppresses the antiferromagnetic order (T_N=2.35K at ambient pressure) and drives the system into a…
We investigate the pressure-temperature phase diagram of YbIr$_2$Si$_2$ by measuring the electrical resistivity $\rho(T)$. In contrast to the widely investigated YbRh$_2$Si$_2$, YbIr$_2$Si$_2$ is a paramagnetic metal below $p_c\simeq 8$…
We report on the first high-resolution dc-magnetisation ($M$) measurements on a single crystal of \ycs. $M$ was measured down to 0.05 K and in fields up to 12 T, with the magnetic field $H$ parallel to the crystallographic direction [100].…
CeRh2As2 has recently been reported to be a rare case of multi-phase unconventional superconductor [S. Khim et al., arXiv:2101.09522] close to a quantum critical point (QCP). Here, we present a comprehensive study of its normal state…
The nature of charge degrees-of-freedom distinguishes scenarios for interpreting the character of a second order magnetic transition at zero temperature, that is, a magnetic quantum critical point (QCP). Heavy-fermion systems are prototypes…
Doping Kondo lattice system CeRu2Si2 with Rh-8% (Ce(Ru0.92Rh0.08)2Si2) leads to drastic consequences due to the mismatch of the lattice parameters between CeRu2Si2 and CeRh2Si2. A large variety of experiments clarifies the unusual…
We summarize existing optical data of URu$_2$Si$_2$ to clarify the nature of the hidden order transition in this heavy fermion metal. Hybridization develops between 50 K and 17.5 K, and a coherent Drude peak emerges which mirrors the…
Hall effect measurements were performed under pressure and magnetic field up to 2.2 GPa and 16 T on a single crystal of UCoAl. At ambient pressure, the system undergoes a first order metamagnetic transition at the critical field B_m = 0.7 T…
We report on the observation of superconductivity in LaRh$_2$As$_2$, which is the analogue without $f$-electrons of the heavy-fermion system with two superconducting phases CeRh$_2$As$_2$. A zero-resistivity transition, a specific-heat jump…
We study the critical behavior of dc magnetization in the uranium ferromagnet URhSi around the paramagnetic to ferromagnetic phase transition at T_C~ 10 K with a modified Arrott plot, a Kouvel-Fisher plot, the critical isotherm analysis and…
In the context of an effective model for doped antiferromagnets, whereby the charge carriers are treated as hard-core bosons, we demonstrate that the ground state energy close to half-filling is an even periodic function of the external…
We report detailed investigation of quantum oscillations in Sr3Ru2O7, observed inductively (the de Haas-van Alphen effect) and thermally (the magnetocaloric effect). Working at fields from 3 T to 18 T allowed us to straddle the metamagnetic…
Electrical resistivity \rho(T) of the 5f ferromagnet UGa2 was investigated for single-crystal samples as a function of pressure and magnetic field. The Curie temperature monotonously increases from T$_{C}$ = 124 K under quasi-hydrostatic…
Despite several decades of both experimental and theoretical work the nature of the hidden order transition at THO = 17.5 K in URu2Si2 remains enigmatic. We report here low field DC magnetization as well as AC susceptibility measurements…
We review the studies on the emergent phases of superconductvity and magnetism in the $f$-electron derived heavy-fermion (HF) systems by means of the nuclear-quadrupole-resonance (NQR) under pressure. These studies have unraveled a rich…
This posting contains raw data used for extracting features of the phase diagram and quantum criticality versus magnetic field $B$, temperature $T$ and Rh-doping $x$ that will soon appear in Physical Review Letters, 2004. All of the raw…
We show that the heavy-fermion compound CeCu2Si2 undergoes a transition between two regimes dominated by different crystal-field states. At low pressure P and low temperature T the Ce 4f electron resides in the atomic crystal-field ground…