Qian Zhang

Two tiny dust grains hover at the crossing of laser beams. Each is held by its own 'tweezer'—a focused beam that keeps the particle from falling. Inside a mirrored cavity, light bounces between the walls, and its oscillations are coupled to the trembling of the grains.

Inside a diamond anvil cell, squeezing a sample with a force millions of times greater than atmospheric pressure, a thin film of lanthanum meets hydrogen. The hydrogen comes from ammonia borane — a powder that, when heated, releases its hydrogen like a sponge releasing water.