Phases of matter are the basic states that matter can take—like water that can occur in a liquid or ice phase. Traditionally, these phases are defined under equilibrium conditions, where the system is stable over time. But nature allows for stranger possibilities: new phases that emerge only when a system is driven out of equilibrium. In a new study published in Nature, a research team shows that quantum computers offer an unparalleled way to explore those exotic states of matter.

Unlike conventional phases of matter, the so-called nonequilibrium quantum phases are defined by their dynamical and time-evolving properties—a behavior that cannot be captured by traditional equilibrium thermodynamics.

One particularly rich class of nonequilibrium states arises in Floquet systems— quantum systems that are periodically driven in time. This rhythmic driving can give rise to entirely new forms of order that cannot exist under any equilibrium conditions, revealing phenomena that are fundamentally beyond the reach of conventional phases of matter.