Non-Abelian Quantum Hall Effect in Topological Flat Bands

Inspired by recent theoretical discovery of robust fractional topological phases without a magnetic field, we search for the non-Abelian quantum Hall effect (NA-QHE) in lattice models with topological flat bands (TFBs). Through extensive numerical studies on the Haldane model with three-body hard-core bosons loaded into a TFB, we find convincing numerical evidence of a stable $\nu=1$ bosonic NA-QHE, with the characteristic three-fold quasi-degeneracy of ground states on a torus, a quantized Chern number, and a robust spectrum gap. Moreover, the spectrum for two-quasihole states also shows a finite energy gap, with the number of states in the lower energy sector satisfying the same counting rule as the Moore-Read Pfaffian state.Comment: 5 pages, 7 figure

2-(4-Hy­droxy­phen­oxy)propanoic acid

In the title compound, C9H10O4, the carboxyl group is oriented at a dihedral angle of 84.6 (3)° with respect to the benzene ring. In the crystal, mol­ecules are linked via O—H⋯O hydrogen bonds

Contingencies of Self-Worth on Positive and Negative Events and Their Relationships to Depression

Previous studies have found that the relationship between contingencies of self-worth (CSW) and depression was generally weak. We posited that this is partly because previous studies assumed CSW on positive and negative events as the same construct (one-dimensional CSW), which should be better conceptualized as two distinctive dimensions (two-dimensional CSW) in explaining depression. A total of 393 undergraduates from Taiwan completed the measures regarding one-dimensional CSW, two-dimensional CSW, and depression. After dividing CSW of seven classic domains into two dimensions of positive and negative CSW, the results of confirmatory factor analyses showed that the two-dimensional CSW model had better model fit than the one-dimensional model in all domains. Furthermore, relative to using one-dimensional CSW as a predictor of depression, the variance accounted for largely increased when positive and negative CSW entered simultaneously in the regression equation. The results suggest that CSW on positive and negative events should be seen as two dimensions and this perspective may largely increase the explanatory power of CSW in explaining mental health

Blue and white phosphorescent organic light emitting diode performance improvement by confining electrons and holes inside double emitting layers

AbstractIn this research, complex emitting layers (EML) were fabricated using TCTA doping hole-transport material in the front half of a bipolar 26DCzPPy as well as PPT doping electron-transport material in the back half of 26DCzPPy. Blue dopant FIrpic was also mixed inside the complex emitting layer to produce a highly efficient blue phosphorescent organic light emitting diode (OLED). The hole and electron injection and carrier recombination rate were effectively increased. The fabricated complex emitting layers exhibited current efficiency of 42cd/A and power efficiency of 30lm/W when the luminance was 1000cd/m2, driving voltage was 4.4V, and current density was 2.4mA/cm2. A white OLED component was then manufactured by doping red dopant [Os(bpftz)2(PPh2Me)2] (Os) in proper locations. When the Os dopant was doped in between the complex emitting layers, excitons were effectively confined within, increasing the recombination rate and therefore reducing the color shift. The resulting Commission Internationale de L’Eclairage (CIE) coordinates shifted from 4 to 10V is (Δx=−0.04, Δy=+0.01). The component had a current efficiency of 35.7cd/A, a power efficiency of 24lm/W, driving voltage of 4.6V and a CIEx,y of (0.31,0.35) at a luminance of 1000cd/m2, with a maximum luminance of 15,600cd/m2 at 10V. Attaching an outcoupling enhancement film was applied to increase the luminance efficiency to 30lm/W

Time-reversal symmetry breaking superconducting ground state in the doped Mott insulator on the honeycomb lattice

The emergence of superconductivity in doped Mott insulators has been debated for decades. In this paper, we report the theoretical discovery of a time-reversal symmetry breaking superconducting ground state in the doped Mott insulator (described by the well known t-J model) on honeycomb lattice, based on a recently developed variational method: the Grassmann tensor product state approach. As a benchmark, we use exact diagonalization and density-matrix renormalization methods to check our results on small clusters. We find systematic consistency for the ground-state energy as well as other physical quantities, such as the staggered magnetization. At low doping, the superconductivity coexists with antiferromagnetic ordering.Comment: 7 pages, 9 figures (published version