Related papers: Valence Instability and Superconductivity in Heavy…
High pressure provides a powerful means for exploring unconventional superconductivity which appears mostly on the border of magnetism. Here we report the discovery of pressure-induced heavy fermion superconductivity up to 2.5 K in the…
In the heavy-fermion materials CeCoIn$_5$ and UBe$_{13}$, the superconducting order parameter is coupled to flucutating magnetization of the uncompensated part of the localized $f$-moments. We find that this coupling decreases the…
Superconductivity has again become a challenge following the discovery of unconventional superconductivity. Resistance-free currents have been observed in heavy-fermion materials, organic conductors and copper oxides. The discovery of…
The pressure-temperature-phase diagram of the new heavy-fermion superconductor CeAu$_2$Si$_2$ is markedly different from those studied previously. Indeed, superconductivity emerges, not on the verge, but deep inside the magnetic phase. In…
In several unconventional superconductors, the highest superconducting transition temperature $T_{c}$ is found in a region of the phase diagram where the antiferromagnetic transition temperature extrapolates to zero, signaling a putative…
The nature of the quantum valence transition is studied in the one-dimensional periodic Anderson model with Coulomb repulsion between f and conduction electrons by the density-matrix renormalization group method. It is found that the…
Magnetism and superconductivity of new heavy fermion compounds CeTIn$_5$ (T=Co, Rh and Ir) are investigated by applying fluctuation exchange approximation to an orbital degenerate Hubbard model. The superconducting phase with…
In this document, I present a personal view on the heavy-fermion problem, within a phenomenological approach guided by experiments. This review presents a set of 'historical' works which established the ground bases of the thematic during…
We review our recent studies on ferromagnetic superconductors, UGe2, URhGe and UCoGe, together with the ferromagnetic quantum criticality and paramagnetic singularity on the Ising 5f-itinerant system UCoAl. Thanks to the variety of ordered…
The study of competing ground states is a central issue in condensed matter physic. In this article we will discuss the interplay of antiferromagnetic order and unconventional superconductivity in Ce based heavy-fermion compounds. In all…
We report measurements of the pressure-dependent superconducting transition temperature $T_c$ and electrical resistivity of the heavy-fermion compound CeCoIn$_5$. Pressure moves CeCoIn$_5$ away from its proximity to a quantum-critical point…
The quantum critical Antiferromagnetic (AFM) fluctuation spectra measured by inelastic neutron scattering recently in two heavy fermion superconductors are used together with their other measured properties to calculate their D-wave…
The heavy fermion properties are reviewed on selected examples often studied in Grenoble. The physical problems are presented as example of exotic matter at low temperature with three major insights: the localisation of the 4f electrons,…
Superconductivity in three dimensions is almost universally governed by Ginzburg-Landau mean field theory, with critical fluctuations typically confined to within a few percent of the transition temperature ($T_{\rm c}$). We report that the…
We investigated the magnetic field dependence of the superconducting phase transition in heavy fermion CeCoIn_5 (T_c = 2.3 K) using specific heat, magneto-caloric effect, and thermal expansion measurements. The superconducting transition…
In this paper the low-temperature properties of two isostructural canonical heavy-fermion compounds are contrasted with regards to the interplay between antiferromagnetic (AF) quantum criticality and superconductivity. For CeCu$_2$Si$_2$,…
We report the novel pressure(P)-temperature(T) phase diagrams of antiferromagnetism (AF) and superconductivity (SC) in CeRhIn$_5$, CeIn$_3$ and CeCu$_2$Si$_2$ revealed by the NQR measurement. In the itinerant helical magnet CeRhIn$_5$, we…
The magnetic ordering temperature of some rare earth based heavy fermion compounds is strongly pressure-dependent and can be completely suppressed at a critical pressure, p$_c$, making way for novel correlated electron states close to this…
On the basis of the Ward-Pitaevskii identity, the residual resistivity $\rho_{0}$ is shown to exhibit huge enhancement around the quantum critical point of valence transition in Ce-based heavy electron systems. This explains a sharp peak of…
Magnetic fluctuations near to quantum criticality can have profound effects. They lead to characteristic scaling at high temperature which may ultimately give way to a reconstruction of the phase diagram and the formation of new phases at…