Strain-tolerant, triangular, monolayer crystals of WS2 were grown on SiO2 substrates patterned with donut-shaped pillars, as shown in scanning electron microscope (bottom) and atomic force microscope (middle) image elements. The curvature of the pillars induced strain in the overlying crystals that locally altered their optoelectronic properties, as shown in bright regions of photoluminescence (top). Credit: Christopher Rouleau/Oak Ridge National Laboratory, US Dept. of Energy A team led by scientists at the Department of Energy's Oak Ridge National Laboratory explored how atomically thin t...