Thomas Linker

In dark interstellar clouds where new stars are born, chemistry starts with a tiny particle — the trihydrogen ion (H₃⁺). It collides with other atoms and sets off a cascade of reactions that build ever more complex molecules. For a long time, it was thought that the main reaction producing it, H₂⁺ colliding with H₂, only happens in the gas phase.

In a boron arsenide crystal, the atoms dance a leisurely dance. After a short light pulse, the lattice begins to vibrate, and these vibrations, known as phonons, redistribute energy so unhurriedly that every step seems measured out in advance.