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A set of dedicated H-mode discharges with constant heating power combining Neutral Beam Injection and Electron Cyclotron Resonance Heating have been executed at the ASDEX Upgrade tokamak using a high triangularity magnetic geometry in order to investigate the impact of filamentary transport to divertor and non-divertor components. The evolution of upstream scrape-off layer (SOL) profiles have been correlated with dedicated separatrix quantities, mostly with the turbulence control parameter $\alpha_{\mathrm{t}}$ (Eich and Manz 2021 Nucl. Fusion 61 086016) describing the turbulence level at the separatrix. With increasing $\alpha_{\mathrm{t}}$ , a broadening of the upstream density profiles in the near-SOL together with the formation of a density shoulder in the far-SOL have been observed. This phenomenon is associated with an enhanced filamentary transport dominating the radial turbulent transport in the far-SOL and confirmed by means of the cooling water calorimetry on non-divertor components. The probe measurements conducted with the ball-pen probe-head mounted on the midplane manipulator and a retarding-field analyzer close to the limiter surface indicate that the key mechanism increasing the radial filamentary transport to the first wall is an increase of the particle flux $\Gamma_\mathrm{r,fil}$ , caused primarily by the packing fraction $f_\mathrm{PF, fil}$ and the filament density $n_\mathrm{e,fil}$ . At the same time, the electron temperature $T_\mathrm{e}$ and ion temperature $T_\mathrm{i}$ measured close to the limiter surface show only small variations above $\alpha_\mathrm{t}$ > 0.5. Both the filamentary heat flux and the gross erosion derived from the first wall probe measurements reach a magnitude that should be considered in the design of future fusion reactors.

We study the charge transport properties of a system of liquid crystal discotic molecules in two distinct phases. To differentiate between the two phases, we use a self-consistent model that describes the pairwise interaction between molecules, the electronic coupling between them and the difference in orbital energies. This multi-scale approach hinges upon having systems that are both accurate (to within atomic resolution) and large (~10,000 molecules). The two phases have dramatically different charge transport network topologies, directly correlated to their molecular structures. We quantify the charge transport on both a macroscopic and microscopic scale, taking advantage of the model's resolution to understand the role of molecular packing in charge transport. [ABSTRACT FROM AUTHOR]

• Stable bipolar resistive switching is observed in Ag/am-BaTiO 3 /ITO capacitor structures. • The SET voltage is found to depend upon the thickness of BaTiO 3 thin films. • Space charge limited current assisted SET process is noted. • The Ag+ ion mediated conduction filament is attributed to the observed bi-polar resistive switching. The electroforming free bipolar resistive switching characteristics of amorphous barium titanate (am-BTO) thin films in Ag/am-BTO/ITO capacitor structures were systematically evaluated. The dot point capacitor structures were fabricated by using RF-DC sputtering deposition on ITO coated commercial glass substrates. Varied thicknesses of 142, 100, and 70 nm am-BTO thin films were utilized as a switching medium for exploring the resistive switching phenomena. The amorphous nature and topographical surface were probed with X-ray diffraction and atomic force microscopy techniques. The on/off resistance ratios, SET, RESET voltages, retention, and endurance parameters extracted from current-voltage (I-V) measurements demonstrate stable resistive switching. Space charge limited current conduction and ohmic conduction phenomena were found to be dominant in high resistance and low states of the junctions. The rupture formation upon the Ag active electrode and reduction in capacitance after the application of voltage specify the silver Ag+ ion mediated filament conduction mechanism for the observed bipolar switching phenomena. [ABSTRACT FROM AUTHOR]