Field-Dependent Hall Effect in Single Crystal Heavy Fermion YbAgGe below 1K

We report the results of a low temperature (T >= 50 mK) and high field (H <= 180 kOe) study of the Hall resistivity in single crystals of YbAgGe, a heavy fermion compound that demonstrates field-induced non-Fermi-liquid behavior near its field-induced quantum critical point. Distinct features in the anisotropic, field-dependent Hall resistivity sharpen on cooling down and at the base temperature are close to the respective critical fields for the field-induced quantum critical point. The field range of the non-Fermi-liquid region decreases on cooling but remains finite at the base temperature with no indication of its conversion to a point for T -> 0. At the base temperature, the functional form of the field-dependent Hall coefficient is field direction dependent and complex beyond existing simple models thus reflecting the multi-component Fermi surface of the material and its non-trivial modification at the quantum critical point

Attachment styles and male sex addiction

This study addresses the adult romantic attachment styles of sexually addicted men. The Sexual Addiction Screening Test and the Experiences in Close Relationships Revised were used to determine the presence of a sexual addiction and the participants’ style of romantic attachment. ANOVA revealed that sexually addicted men are more likely to relate with insecure attachment styles. Specifically, sexually addicted men were found to have higher anxiety F(1, 38) = 6.122, p \u3c .05 and avoidance F(1, 37) = 4.685, p \u3c .05 in their romantic relationships. Treatment for male sexual addicts should address both addiction and relationship insecurity

catena-Poly[[diazido­zinc(II)]-μ-di-4-pyridylamine-κ2 N:N′]

In the title compound, [Zn(N3)2(C10H9N3)]n, tetra­hedrally coordinated ZnII ions with two monodentate azide ligands are linked into zigzag one-dimensional chain motifs by di-4-pyridylamine (dpa) tethers. Individual [Zn(N3)2(dpa)]n chains are connected into supra­molecular layers via N—H⋯N hydrogen bonding between the central amine groups of the dpa ligands and terminal unligated azide N atoms. The azide ligands in one supra­molecular layer penetrate through the neighboring layers above and below, allowing stacking into a three-dimensional structure

Poly[[diaqua­bis(μ3-maleato-κ4 O 1:O 1′,O 4:O4′)dicopper(II)] trihydrate]

In the title compound, {[Cu2(C4H2O4)2(H2O)2]·3H2O}n, CuII ions with square-pyramidal coordination are bridged by exo­tri­dentate maleate dianions into [Cu2(maleate)2(H2O)2]n layers coincident with the bc crystal plane. The inter­lamellar regions contain hydrogen-bonded cyclic water hexa­mers which facilitate layer stacking into a pseudo-three-dimensional crystal structure. The water hexamers themselves are formed by the operation of crystallographic inversion centers on sets of three crystallographically distinct water molecules of hydration

Attachment styles and male sex addiction

This study addresses the adult romantic attachment styles of sexually addicted men. The Sexual Addiction Screening Test and the Experiences in Close Relationships Revised were used to determine the presence of a sexual addiction and the participants’ style of romantic attachment. ANOVA revealed that sexually addicted men are more likely to relate with insecure attachment styles. Specifically, sexually addicted men were found to have higher anxiety F(1, 38) = 6.122, p \u3c .05 and avoidance F(1, 37) = 4.685, p \u3c .05 in their romantic relationships. Treatment for male sexual addicts should address both addiction and relationship insecurity

4,4′-Imino­dipyridinium bis­(hydrogen phthalate)

In the title salt, C10H11N3 2+·2C8H5O4 −, doubly protonated 4,4′-dipyridylamine (dpa) cations participate in N—H⋯O hydrogen bonding with two hydrogen phthalate anions to form a neutral unit. Both anions contain an intramolecular O—H⋯O hydrogen bond. In the crystal structure, these units form two-dimensional layers through π–π stacking inter­actions with a centroid-to-centroid distance of 3.763 (3) Å. In turn, these layers aggregate in three dimensions by additional N—H⋯O hydrogen bonding. The assignment to the noncentrosymmetric space group P1 is corroborated by chemically unreasonable aromatic ring bond distances and poor K scale factor distributions for a disordered model in the centrosymmetric P space group

A direct measurement of the Bose-Einstein Condensation universality class in NiCl2_2-4SC(NH2_2)2_2 at ultra-low temperatures

In this work, we demonstrate field-induced Bose-Einstein condensation (BEC) in the organic compound NiCl$_2$-4SC(NH$_2$)$_2$ using AC susceptibility measurements down to 1 mK. The Ni \textsl{S}=1 spins exhibit 3D $\mathit{XY}$ antiferromagnetism between a lower critical field $H_{c1} \sim$ 2 T and a upper critical field $H_{c2} \sim$ 12 T. The results show a power-law temperature dependence of the phase transition line $H_{c1} (T) -H_{c1} (0) = aT^{\alpha}$ with $\alpha =$ 1.47$\pm$0.10 and $H_{c1} (0) = 2.053$ T, consistent with the 3D Bose-Einstein Condensation universality class. An abnormal change was found in the phase boundary near $H_{c2}$ at approximately 150 mK.Comment: 4 pages, 4 figure

Quasiparticle spectroscopy and high-field phase diagrams of cuprate superconductors -- An investigation of competing orders and quantum criticality

We present scanning tunneling spectroscopic and high-field thermodynamic studies of hole- and electron-doped (p- and n-type) cuprate superconductors. Our experimental results are consistent with the notion that the ground state of cuprates is in proximity to a quantum critical point (QCP) that separates a pure superconducting (SC) phase from a phase comprised of coexisting SC and a competing order, and the competing order is likely a spin-density wave (SDW). The effect of applied magnetic field, tunneling current, and disorder on the revelation of competing orders and on the low-energy excitations of the cuprates is discussed.Comment: 10 pages, 5 figures. Accepted for publication in the International Journal of Modern Physics B. (Correspondence author: Nai-Chang Yeh, e-mail: [email protected]

Coexistence of antiferromagnetic order and unconventional superconductivity in heavy fermion compounds CeRh_{1-x}Ir_xIn_5: nuclear quadrupole resonance studies

We present a systematic ^{115}In NQR study on the heavy fermion compounds CeRh_{1-x}Ir_xIn_5 (x=0.25, 0.35, 0.45, 0.5, 0.55 and 0.75). The results provide strong evidence for the microscopic coexistence of antiferromagnetic (AF) order and superconductivity (SC) in the range of 0.35 \leq x \leq 0.55. Specifically, for x=0.5, T_N is observed at 3 K with a subsequent onset of superconductivity at T_c=0.9 K. T_c reaches a maximum (0.94 K) at x=0.45 where T_N is found to be the highest (4.0 K). Detailed analysis of the measured spectra indicate that the same electrons participate in both SC and AF order. The nuclear spin-lattice relaxation rate 1/T_1 shows a broad peak at T_N and follows a T^3 variation below T_c, the latter property indicating unconventional SC as in CeIrIn_5 (T_c=0.4 K). We further find that, in the coexistence region, the T^3 dependence of 1/T_1 is replaced by a T-linear variation below T\sim 0.4 K, with the value \frac{(T_1)_{T_c}}{(T_1)_{low-T}} increasing with decreasing x, likely due to low-lying magnetic excitations associated with the coexisting magnetism.Comment: 20 pages, 14 figure