Category Physics

A schematic drawing of how a ring of exceptional points (shown in white) can be spawned from a Dirac point (a dot), and thus change the dispersion from the normal, widely known conical shape into an exotic lantern-like shape Credit: Courtesy of the researchers

Couplings of the gadolinium spin system. (a) The interaction of the different heat baths in an extended three-temperature model. After infrared laser excitation of the valence electrons, the whole system equilibrates by exchanging energy and momentum, indicated by the double arrows. The 5d and 4f spin systems couple via inter- and intra-atomic exchange, where the intra-atomic exchange Jint=130 meV is much larger than the largest (nearest neighbour) inter-atomic exchange Jij=5.9 meV. In thermal equilibrium, the combination of inter- and intra-atomic exchange interactions mediates spin order in the 4f system via the delocalized 5d valence bands...

The Celeste graphical model. Shaded vertices represent observed random variables. Empty vertices represent latent ran- dom variables. Black dots represent constants. Constants denoted by uppercase Greek characters are fixed and denote parameters of prior distributions. The remaining constants and all latent random variables are inferred.

(a) Coupling efficiency (ηC) versus source angle (φ) for a planar solar panel. The panel projected area decreases with the cosφ. (b) A kirigami tracking structure that, upon stretching, simultaneously changes the angle of the elements comprising the sheet. By incorporating thin-film solar cells into this structure, it may be used as a low-profile alternative to conventional single-axis solar tracking. (c) The direction of feature tilt (that is, clockwise or counter-clockwise with respect to the original plane) is controlled by lifting or lowering one end of the sheet (step 1) before the straining process (step 2).