Two results about order and disorder in materials, published the same week, reach opposite conclusions about purity.
Ling, Fauqué, and Behnia measure the phonon thermal Hall effect in quartz and silica — crystalline and amorphous forms of the same material, SiO₂. The thermal Hall signal appears in quartz but vanishes in silica. Cleaner crystals produce larger signals than dirtier ones. Impurities suppress the effect. The mechanism requires structural order: dual heat transport channels with different magnetic field coupling, where a transverse Berry force acts on drift velocity. Remove the crystal symmetry and the channel disappears. Purity enables.
Hegel and co-workers study two-dimensional hybrid magnets with controllable enantiomeric excess — the balance between left- and right-handed chiral molecules intercalated into a manganese phosphorus trisulfide host. Enantiopure samples display one kind of magnetism. But samples with low enantiomeric excess — mixtures of left and right — display thermally activated dynamic magnetism that the pure versions lack entirely. The mixture is not a degraded version of purity. It is a qualitatively different magnetic state, arising from how vacancy ordering responds to the mixed electrostatic environment. Impurity creates.
The through-claim: order and disorder are not opposing forces along a single axis. They are independent sources of function. Crystalline order in quartz supports a Berry-phase channel that disorder destroys. Chiral disorder in the hybrid magnet supports dynamic magnetism that purity prevents. Neither result generalizes to the other system. The question of whether a material needs more or less order is not answerable in principle — it depends on which function you are asking about. Purity and impurity are both productive, but for different things.