Related papers: Missing spectral weight in a heavy-fermion system …
Strange metals defy the quasiparticle description of conventional metals, exhibiting a linear in temperature ($T$-linear) resistivity in a broad temperature range. It has become increasingly clear that, together with $T$-linear resistivity,…
Quantum criticality in cubic heavy fermion compounds remains much less explored than in quasi-two-dimensional systems. However, such materials are needed to broadly test the recently suggested global phase diagram for heavy fermion quantum…
Quantum phase transitions arise in many-body systems due to competing interactions that promote rivaling ground states. Recent years have seen the identification of continuous quantum phase transitions, or quantum critical points, in a host…
Effects of a charge-density-wave (CDW) order on the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction has been theoretically investigated. Assuming that the CDW with an incommensurate ordering vector ${\bf Q}_c$ is induced by a Fermi surface…
We propose that real-space properties of the two-impurity Kondo model can be obtained from an effective spin model where two single-impurity Kondo spin chains are joined via an RKKY interaction between the two impurity spins. We then use a…
The competition between magnetic order and Kondo effect is essential for the rich physics of heavy fermion systems. Nevertheless, how such competition is manifested in the quasiparticle bands in a real periodic lattice remains elusive in…
Carrier-mediated ferromagnetism in a dilute magnetic semiconductor has been studied using i) a single-impurity based generalized RKKY approach which goes beyond linear response theory, and ii) a mean-field-plus-spin-fluctuation (MF+SF)…
The cooperative behavior of quantum impurities on 2D materials, such as graphene and bilayer graphene, is characterized by a non-trivial competition between screening (Kondo effect), and Ruderman-Kittel-Kasuya-Yosida (RKKY) magnetism. In…
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…
Quasi-particle spin susceptibility ($\chi^{qp}$) for various heavy-fermion (HF) superconductors are discussed on the basis of the experimental results of electronic specific heat ($\gamma_{el}$), NMR Knight shift ($K$) and NMR relaxation…
We review the anomalous properties of heavy fermion compounds like CeCu$_{6-x}$Au$_x$ or CeMIn$_5$ close to a zero temperature phase transition called a quantum critical point. Anomalous behavior of the resistivity, specific heat and…
Recent studies of heavy-fermion systems with tunable quantum fluctuations have focused on a variety of zero-temperature phase transitions that involve not only the onset of magnetic order but also the destruction of Kondo entanglement.…
The existence of multiple energy scales is regarded as a signature of the Kondo breakdown mechanism for explaining the quantum critical behavior of certain heavy fermion compounds, like YbRh$_{2}$Si$_{2}$. The nature of the intermediate…
It has been suggested recently by Gan, Coleman, and Andrei that studying the underscreened Kondo problem may help to understand the nature of magnetism in heavy fermion systems. Motivated by Doniach's work on the S=1/2 Kondo necklace, we…
In this work, we use the numerical renormalization group (NRG) theory to study the thermodynamics of the two-impurity Anderson model. Two different methods are used to estimate the effect of the Dzyaloshiskii-Moriya (DM) interaction on the…
Nanoscale systems of metal atoms antiferromagnetically exchange coupled to several magnetic impurities are shown to exhibit an unconventional re-entrant competition between Kondo screening and indirect magnetic exchange interaction.…
Linear CoCu_nCo clusters on Cu(111) are fabricated by means of atomic manipulation. They represent a two-site Kondo system with tunable interaction. Scanning tunneling spectroscopy reveals oscillations of the Kondo temperature T_K with the…
In heavy-fermion systems, the competition between the local Kondo physics and intersite magnetic fluctuations results in unconventional quantum critical phenomena which are frequently addressed within the Kondo lattice model (KLM). Here we…
The main properties and the type of the field-tuned quantum critical point in the heavy-fermion metal CeCoIn$_5$ arisen upon applying magnetic fields $B$ are considered within the scenario based on the fermion condensation quantum phase…
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…