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Low-dimensional systems host many exotic physical properties. Using extended resonant soft x-ray scattering supported with theoretical calculations, we observe concomitantly a Wigner-like crystal in a stripe-like QHKL = (001) superlattice with surprisingly long coherence lengths and new soft x-ray correlated plasmons in WS2. A new electronic transition is found at 125 K upon cooling, which is a transition from two-dimensional ordering to three-dimensional ordering, a result of p–d hybridization anisotropy and electronic correlations. Our result shows the importance of the interplay of long-range electron–electron correlation and short-range electronic screening in determining electronics and optical properties of transition metal dichalcogenides. [ABSTRACT FROM AUTHOR]

1:CAS:528:DyaE1MXkvVWju70%3D. 10.1088/0022-3719/12/5/017 3 Habenicht C, Knupfer M, Büchner B. Investigation of the dispersion and the effective masses of excitons in bulk MoS2 using transition electron energy-loss spectroscopy. 4 of the main manuscript are caused by electron-electron interactions, but do not cause electron correlations, which can be seen in the large spectral weight transfer in Fig. Even at room temperature, the effective mass of electrons in crystals is not always equal to the single electron mass, I m i SB 0 sb [11], including in TMDCs[14]. We hope we have settled or answered most, if not all, of the issues presented in the Matters Arising and our result opens discussions on roles of electronic correlation on effective mass of electron, electronic and optical structures in strongly correlated electron systems. [Extracted from the article]

Poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) PEDOT : PSS is extensively used as a hole injection layer (HIL) in solution-processed organic light emitting diodes (OLEDs). The high work function of a HIL is crucial in improving OLED efficiency. The work function of PEDOT : PSS is usually around 5.1–5.3 eV. By adding perfluorinated ionomer (PFI), the work function of PEDOT : PSS has been reported to reach as high as 5.95 eV. We investigated the effects of PFI-modified PEDOT : PSS in a single-layer solution-processed blue phosphorescent OLED (PHOLED). We observed that high concentrations of a PFI in PEDOT : PSS has detrimental effects on the device efficiency due to the low conductivity of the PFI. Using this approach, blue PHOLEDs with efficiencies of 9.4 lm W−1 (18.2 cd A−1) and 7.9 lm W−1 (20.4 cd A−1) at 100 cd m−2 and 1000 cd m−2, respectively, were demonstrated. [ABSTRACT FROM AUTHOR]