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تسجيل مستخدم جديدProtocol to engineer Fulde-Ferrell-Larkin-Ovchinnikov states in a cold Fermi gas
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We propose a two-step experimental protocol to directly engineer Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) states in a cold two-component Fermi gas loaded into a quasi-one-dimensional trap. First, one uses phase imprinting to create a train of domain walls in a superfluid with equal number of $uparrow$- and $downarrow$-spins. Second, one applies a radio-frequency sweep to selectively break Cooper pairs near the domain walls and transfer the $uparrow$-spins to a third spin state which does not interact with the $uparrow$- and $downarrow$-spins. The resulting FFLO state has exactly one unpaired $downarrow$-spin in each domain wall and is stable for all values of domain-wall separation and interaction strength. We show that the protocol can be implemented with high fidelity at sufficiently strong interactions for a wide range of parameters available in present-day experimental conditions.
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