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تسجيل مستخدم جديدMultiple particle-hole pair creation in the Fermi-Hubbard model by a pump laser
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We study the Fermi-Hubbard model in the strongly correlated Mott phase under the influence of a harmonically oscillating electric field, e.g., a pump laser. In the Peierls representation, this pump field can be represented as an oscillating phase of the hopping rate $J(t)$, such that the effective time-averaged rate $bar J$ is reduced, i.e., switching the pump laser suddenly is analogous to a quantum quench. Apart from this time-averaged rate $bar J$, it is well known that the oscillating component of $J(t)$ can resonantly create particle-hole pairs if the pump frequency $omega_{rm pump}$ equals (or a little exceeds) the Mott gap. In addition, we find that it is possible to create multiple pairs if $omega_{rm pump}$ is near an integer multiple of the gap. These findings should be relevant for pump-probe experiments.
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