Related papers: Element-specific probe of quantum criticality in $…
Understanding the origin of superconductivity in strongly correlated electron systems continues to be at the forefront of unsolved problems in all of physics. Among the heavy f-electron systems, CeCoIn5 is one of the most fascinating, as it…
We report measurements of the magnetic penetration depth $\lambda$ in single crystals of CeCoIn$_{5}$ down to $\sim$0.14 K using a tunnel-diode based, self-inductive technique at 28 MHz. While the in-plane penetration depth tends to follow…
Quantum criticality in the normal and superconducting state of the heavy-fermion metal CeCoIn$_5$ is studied by measurements of the magnetic Gr\"{u}neisen ratio, $\Gamma_H$, and specific heat in different field orientations and temperatures…
CeIrSn with a quasikagome Ce lattice in the hexagonal basal plane is a strongly valence fluctuating compound, as we confirm by hard x-ray photoelectron spectroscopy and inelastic neutron scattering, with a high Kondo temperature of…
The importance of antiferromagnetic fluctuations are widely acknowledged in most unconventional superconductors. In addition, cuprates and iron pnictides often exhibit unidirectional (nematic) electronic correlations, including stripe and…
We present results of specific heat, electrical resistance, and magnetoresistivity measurements on single crystals of the heavy-fermion superconducting alloy Ce$_{0.91}$Yb$_{0.09}$CoIn$_5$. Non-Fermi liquid to Fermi liquid crossovers are…
We report $^{115}$In nuclear magnetic resonance (NMR) measurements in CeCoIn$_5$ at low temperature ($T \approx 70$ mK) as a function of magnetic field ($H_0$) from 2 T to 13.5 T applied perpendicular to the $\hat c$-axis. NMR line shift…
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,…
We report In-NQR and Co-NMR experiments of CeCoIn$_5$ that undergoes a superconducting transition with a record high $T_{\rm c}$ = 2.3 K to date among heavy-fermion superconductors. At zero magnetic field, an anomalous temperature ($T$)…
We report $^{115}$In nuclear quadrupolar resonance (NQR) measurements on the heavy-fermion superconductor PuCoIn$_5$, in the temperature range $0.29{\rm K}\leq T\leq 75{\rm K}$. The NQR parameters for the two crystallographically…
We report on systematic evolutions of antiferromagnetic (AFM) spin fluctuations and unconventional superconductivity (SC) in heavy-fermion (HF) compounds CeRh$_{1-x}$Ir$_{x}$In$_5$ via $^{115}$In nuclear-quadrupole-resonance (NQR)…
We demonstrate that the thermopower (S) can be used to probe the spin fluctuations (SFs) in proximity to the quantum critical point (QCP) in Fe-based superconductors. The sensitivity of S to the entropy of charge carriers allows us to…
CePd_1-xRh_x alloys exhibit a continuous evolution from ferromagnetism (T_C= 6.5 K) at x = 0 to a mixed valence (MV) state at x = 1. We have performed a detailed investigation on the suppression of the ferromagnetic (F) phase in this alloy…
Electrical resistivity measurements on a single crystal of the heavy-fermion superconductor CeCoIn_5 at pressures to 4.2 GPa reveal a strong crossover in transport properties near P^* \approx 1.6 GPa, where T_c is a maximum. The…
In the generic phase diagram of heavy fermion systems, tuning an external parameter such as hydrostatic or chemical pressure modifies the superconducting transition temperature. The superconducting phase forms a dome in the…
The nature of quantum criticality in CeCoIn$_5$ is studied by low-temperature thermal expansion $\alpha(T)$. At the field-induced quantum critical point at H=5 T a crossover scale $T^\star\approx 0.3$ K is observed, separating…
Quantum-mechanical fluctuations in strongly correlated electron systems cause unconventional phenomena such as non-Fermi liquid behavior, and arguably high temperature superconductivity. Here we report the discovery of a field-tuned quantum…
Motivated by recent experiments reporting superconductivity only at very low temperature in a class of heavy fermion compounds, we study the impact of energy fluctuations with small momentum transfer on the pairing instability near an…
We report the Nernst effect (v) and thermoelectric power (S) data for the Ce2PdIn8 heavy-fermion compound. Both S and v behave anomalously at low temperatures: the thermopower shows a Kondo-like maximum at T = 37 K, while the Nernst…
High quality single crystals of heavy Fermion CeCoIn5 superconductor have been grown by flux method with a typical size of (1~2)mm x (1~2)mm x ~0.1 mm. The single crystals are characterized by structural analysis from X-ray diffraction and…