Related papers: Quantum critical 5f-electrons avoid singularities …
The term "hidden order" refers to an as yet unidentified form of broken-symmetry order parameter that is presumed to exist in the strongly correlated electron system URu2Si2 on the basis of the reported similarity of the heat capacity at…
Heavy fermion compounds exhibiting a ferromagnetic quantum critical point have attracted considerable interest. Common to two known cases, i.e., CeRh$_6$Ge$_4$ and YbNi$_4$P$_2$, is that the 4f moments reside along chains with a large…
We propose a candidate for the hidden order in URu2Si2: a rank-5 E type spin density wave between Uranium 5f crystal field doublets breaking time reversal and lattice tetragonal symmetry in a manner consistent with recent torque…
We study the structural and magnetic orders in electron-doped BaFe2-xNixAs2 by high-resolution synchrotron X-ray and neutron scatterings. Upon Ni-doping x, the nearly simultaneous tetragonal-to-orthorhombic structural T_s and…
The hidden order (HO) in URu2Si2 has been determined as a high rank multipole formed by itinerant 5f-electrons with distinct orbital structure imposed by the crystalline electric field. Because this can lead to a considerable number of…
We report the high-field induced magnetic phase in single crystal of U(Ru0.92Rh0.08)2Si2. Our neutron study combined with high-field magnetization, shows that the magnetic phase above the first metamagnetic transition at Hc1 = 21.6 T has an…
The large $\Delta$C observed at 17.5 K in URu$_{2}$Si$_{2}$ is inconsistent with the small, 0.04 $\mu_{B}$ moment measured for the antiferromagnetism observed starting (perhaps coincidentally) at the same temperature. We report measurements…
Neutron-scattering and specific-heat measurements of the heavy-fermion superconductor URu2Si2 under hydrostatic pressure and with Rh-doping [U(Ru{0.98}Rh{0.02})2Si2] show the existence of two magnetic phase transitions. At the second-order…
We have studied the ultrasonic velocity and ac susceptibility of $URu_2Si_2$ in d. c. magnetic fields up to 45T. A significant difference between the constructed H-T phase diagram and that extracted from earlier pulsed fields measurements…
Structural phase transitions in $f$-electron materials have attracted sustained attention both for practical and basic science reasons, including that they offer an environment to directly investigate relationships between structure and the…
Low temperature magnetization M measurements down to 70~mK have been performed through the superconducting upper critical field H_c2 of CeCoIn5 with the field H parallel to the c axis of the tetragonal crystal. The crossing through the…
Thermoelectric power ($S$) and Hall effect ($R_\mathrm{H}$) measurements on the paramagnetic superconductor UTe$_2$ with magnetic field applied along the hard magnetization $b$-axis are reported. The first order nature of the metamagnetic…
Transport, magnetic and thermal properties at high magnetic fields (H) and low temperatures (T) of the heavy fermion compound CeAuSb_2 are reported. At H=0 this layered system exhibits antiferromagnetic order below T_N = 6 K. Applying B…
We examine the degree of 5f electron localization in URu2Si2 using spin-orbit sum rule analysis of the U N4,5 (4d \to 5f) edge. When compared to {\alpha}-U metal, US, USe, and UTe, which have increasing localization of the 5f states, we…
The pressure--temperature phase diagram of CeRhIn_5 has been studied under high magnetic field by resistivity measurements. Clear signatures of a quantum critical point has been found at a critical pressure of p_c = 2.5 GPa. The field…
To elucidate the underlying nature of the hidden order (HO) state in heavy-fermion compound URu2Si2, we measure electrical transport properties of ultraclean crystals in a high field/low temperature regime. Unlike previous studies, the…
Electrical resistivity measurements were performed on single crystals of URu$_2-x$Os$_x$Si$_2$ up to $x$ = 0.28 under hydrostatic pressure up to $P$ = 2 GPa. As the Os concentration, $x$ , is increased, (1) the lattice expands, creating an…
The nature of the antiferromagnetic order in the heavy fermion metal YbRh$_2$Si$_2$, its quantum criticality, and superconductivity, which appears at low mK temperatures, remain open questions. We report measurements of the heat capacity…
Recently, in high-T_c superconductors (HTSC), exciting measurements have been performed revealing their physics in superconducting and pseudogap states and in normal one induced by the application of magnetic field, when the transition from…
In a recent publication [M. B. Stone et al., New Journal of Physics 9, 31 (2007)] a "Renormalized Classical 2D" (RC) phase has been reported in a quasi-two-dimensional quantum antiferromagnet PHCC. Its key signature is a sharp cusp-like…