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تسجيل مستخدم جديدCooling by photo-doping $--$ Light-induced symmetry breaking in the Hubbard model
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An elusive goal in the field of driven quantum matter is the induction of long-range order. Here, we demonstrate a mechanism based on light-induced evaporative cooling of holes in a correlated electron system. Since the entropy of a filled narrow band grows rapidly with hole doping, the isentropic transfer of holes from a doped Mott insulator to such a band results in a drop of temperature. Strongly correlated Fermi liquids and symmetry-broken states could thus be produced by dipolar excitations. Using nonequilibrium dynamical mean field theory, we show that suitably designed chirped pulses allow to realize this cooling effect. In particular, we demonstrate the emergence of antiferromagnetic order in a system which is initially in a weakly correlated state above the maximum Neel temperature. Our work suggests a general strategy for inducing strong correlation phenomena and electronic orders in light-driven materials or periodically modulated atomic gases in optical lattice potentials.
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