Category: 4. Physics
-
Three types of bidirectional leader development in triggered lightning flashes
The eight cases were contained in six negative triggered lightning flashes, of which one was the altitude-triggered lightning flash and the other five were classical triggered lightning flashes. Except for the triggering type of each flash, Table 1 lists the numbers of return strokes (RSs), the peak value of the studied RSs current, the observation…
-
Dual plasmonic modes in the visible light region in rectangular wave-shaped surface relief plasmonic gratings
Long-range surface plasmon resonance characteristics Figure 4a shows the reflectance spectra measured from the diffracted beams of an RSR-PG sample. The RSR-PG structure was placed at various incident angles, namely 45°, 50°, 55°, or 60° normal to the RSR-PG surface. The photodetector then sequentially measured the reflectance beam at various angles normal to the RSR-PG surface,…
-
Passive atomic-scale optical sensors for mapping light flux in ultra-small cavities
Four rock cores were first irradiated with gamma rays to create trapped electrons (mapped using IRPL), and then cut in half along the axis. Cracks of different widths were simulated by placing spacers between the two halves. All these steps were done under dark conditions. The ‘cracked’ rock cores were then positioned under a solar…
-
Spinful hinge states in the higher-order topological insulators WTe2
Multilayer Td-WTe2 has a noncentrosymmetric orthorhombic structure belonging to the SG 31 (Pmn21) space group with two perpendicular axes (a– and b-axis) and one mirror line along the b-axis (Fig. 1a). Together with the time-reversal symmetry, this spatial mirror symmetry satisfies necessary prerequisites to support the topologically non-trivial spin-polarized helical hinges26,28. In our experiments, multilayer WTe2…
-
Twin-pulse seeding enables pump-probe capabilities in the EUV to soft X-ray spectrum at synchrotron light sources
Feasibility study of an adjustable two-stage separation Seeding coherent EUV to soft X-ray emission can be accomplished using a compact EEHG design via two SSs of a SR1,2. This design utilizes the BM section between these two SSs as the first chicane. However, one of the key EEHG parameters, the momentum compaction of chicane 1,…
-
Motility-induced phase separation is reentrant
Theoretical analysis We start from a minimal active fluid theory characterizing MIPS from a kinetics approach21,22,38. The theory describes the steady state of phase separation with a dense clustering phase which is set as close packed and a dilute phase as homogeneous and isotropic. Particles transport between two phases through condensation and evaporation events with…
-
Tunnelling electrons locally ignite excitons
Tunnelling electrons locally ignite excitons Continue Reading News Source: www.nature.com
-
Defect modeling and control in structurally and compositionally complex materials
Pantelides, S. T. The electronic structure of impurities and other point defects in semiconductors. Rev. Mod. Phys. 50, 797–858 (1978). Article Google Scholar Estreicher, S. K. Hydrogen-related defects in crystalline semiconductors: a theorist’s perspective. Mater. Sci. Eng. R. Rep. 14, 319–412 (1995). Article Google Scholar Kim, H. & Chelikowsky, J. R. Theoretical scanning tunneling microscopy…
-
Substrate effects on spin relaxation in two-dimensional Dirac materials with strong spin-orbit coupling
First-principles density-matrix dynamics for spin relaxation We solve the quantum master equation of density-matrix \(\rho \left(t\right)\) as the following20: $$\begin{array}{ll}\dfrac{d{\rho }_{12}\left(t\right)}{dt}\,=\,-\dfrac{i}{\hslash }{\left[{H}_{e},\rho \left(t\right)\right]}_{12}\,+\,\left(\begin{array}{c}\frac{1}{2}{\sum }_{345}\left\{\begin{array}{c}{\left[I-\rho \left(t\right)\right]}_{13}{P}_{32,45}{\rho }_{45}\left(t\right)\\ -{\left[I-\rho \left(t\right)\right]}_{45}{P}_{45,13}^{* }{\rho }_{32}\left(t\right)\end{array}\right\}\\ +H.C.\end{array}\right),\end{array}$$ … Continue Reading News Source: www.nature.com
-
Accelerating the design of compositionally complex materials via physics-informed artificial intelligence
Raabe, D., Tasan, C. C. & Olivetti, E. A. Strategies for improving the sustainability of structural metals. Nature 575, 64–74 (2019). Article Google Scholar Olivetti, E. A. & Cullen, J. M. Toward a sustainable materials system. Science 360, 1396–1398 (2018). Article Google Scholar Reed, R. C. The Superalloys (Cambridge Univ. Press, 2009); https://doi.org/10.1017/cbo9780511541285 Suzuki, A.,…