Related papers: Multiple energy scales at a quantum critical point
Quantum critical phenomena are widely studied across various materials families, from high temperature superconductors to magnetic insulators. They occur when a thermodynamic phase transition is suppressed to zero temperature as a function…
Magnetic fluctuations and electrons couple in intriguing ways in the vicinity of zero temperature phase transitions - quantum critical points - in conducting materials. Quantum criticality is implicated in non-Fermi liquid behavior of…
We have studied the evolution of the weakly first order antiferromagnetic transition in heavy fermion Yb$_3$Pt$_4$ using a combination of specific heat, magnetic susceptibility, and electrical resistivity experiments. We show that magnetic…
We present results of high-resolution, low-temperature measurements of the Hall coefficient, thermopower, and specific heat on stoichiometric YbRh2Si2. They support earlier conclusions of an electronic (Kondo-breakdown) quantum critical…
We present quantum oscillations observed in the heavy fermion compound YbPtBi in magnetic fields far beyond its field-tuned, quantum critical point. Quantum oscillations are observed in magnetic fields as low as 60 kOe at 60 mK and up to…
Dilation and thermopower measurements on YbAgGe, a heavy-fermion antiferromagnet, clarify and refine the magnetic field-temperature (H-T) phase diagram and reveal a field-induced phase with T-linear resistivity. On the low-H side of this…
The heavy fermion compound YbRh$_2$Si$_2$ is studied by low-temperature magnetization $M(T)$ and specific-heat $C(T)$ measurements at magnetic fields close to the quantum critical point ($H_c=0.06$ T, $H\perp c$). Upon approaching the…
The magnetoresistance (MR) of CeCoIn_5 is notably different from that in many conventional metals. We show that a pronounced crossover from negative to positive MR at elevated temperatures and fixed magnetic fields is determined by the…
A quantum critical point (QCP) is a singularity in the phase diagram arising due to quantum mechanical fluctuations. The exotic properties of some of the most enigmatic physical systems, including unconventional metals and superconductors,…
We use inelastic neutron scattering to measure the magnetic fluctuations in a single crystal of the heavy fermion alloy CeCu_5.9Au_0.1 close to the antiferromagnetic quantum critical point. The energy and temperature-dependent spectra obey…
We use the recently developed critical quasiparticle theory to derive the scaling behavior associated with a quantum critical point (QCP) in a correlated metal. This is applied to the magnetic-field induced QCP observed in YbRh$_2$Si$_2$…
We report measurements of the low temperature magnetization $M$ and specific heat $C$ as a function of temperature and magnetic field of the quasi-one-dimensional spin chain, heavy fermion compound YbFe$_5$P$_3$, which resides close to a…
The interpretation of the magnetic phase diagrams of strongly correlated electron systems remains controversial. In particular, the physics of quantum phase transitions, which occur at zero temperature, is still enigmatic. Heavy-fermion…
Recent experimental studies have revealed an abrupt change in the Hall number at a field tuned quantum critical point in the heavy fermion magnet YbRh2Si2. We investigate this by calculating the local density band structure for this metal…
We report spontaneous appearance of antiferromagnetic order in a model gapped quantum paramagnet Ni(Cl$_{1-x}$Br$_x$)$_2$$\cdot$4SC(NH$_2$)$_2$ induced by a change in bromine concentration x. This transition is qualitatively similar to a z…
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…
We present temperature and field dependent heat capacity and magnetization data taken at temperatures down to 50 mK and in an applied magnetic field up to 11.5 Tesla for YbAgGe, a heavy-fermion compound with a field induced quantum critical…
We report on precise low-temperature specific-heat measurements, C(T), of YbRh2Si2 in the vicinity of the antiferromagnetic phase transition on a single crystal of superior quality (RRR 150). We observe a very sharp peak at T_N=72mK with…
We report measurements of magnetic quantum oscillations and specific heat at low temperatures across a field-induced antiferromagnetic quantum critical point (QCP)(B_{c0}\approx50T) of the heavy-fermion metal CeRhIn_5. A sharp…
The point at absolute zero where matter becomes unstable to new forms of order is called a quantum critical point (QCP). The quantum fluctuations between order and disorder that develop at this point induce profound transformations in the…