Nonequilibrium charge-density-wave order beyond the thermal limit

Abstract The interaction of many-body systems with intense light pulses may lead to novel emergent phenomena far from equilibrium. Recent discoveries, such as the optical enhancement critical temperature in certain superconductors and photo-stabilization hidden phases, have turned this field into an important research frontier. Here, we demonstrate nonthermal charge-density-wave (CDW) order at electronic temperatures greater than thermodynamic transition temperature. Using time- angle-resolved photoemission spectroscopy time-resolved X-ray diffraction, investigate structural parameters ultrafast photoinduced CDW-to-metal transition. Tracking dynamical CDW recovery a function reveals behaviour markedly different equilibrium, which attribute suppression lattice fluctuations transient phonon distribution. A complete description system’s coherent incoherent order-parameter dynamics is given by time-dependent Ginzburg-Landau framework, providing access potential energy surfaces.