Unconventional fermionic pairing states in a monochromatically tilted optical lattice
Nocera, A.; Polkovnikov, A.; Feiguin, A. E.
We study the one-dimensional attractive fermionic Hubbard model under the influence of periodic driving with
the time-dependent density matrix renormalization group method. We show that the system can be driven into
an unconventional pairing state characterized by a condensate made of Cooper pairs with a finite center-of-mass
momentum similar to a Fulde-Ferrell state. We obtain results both in the laboratory and the rotating reference
frames demonstrating that the momentum of the condensate can be finely tuned by changing the ratio between
the amplitude and the frequency of the driving. In particular, by quenching this ratio to the value corresponding to
suppression of the tunneling and the Coulomb interaction strength to zero, we are able to “freeze” the condensate.
We finally study the effects of different initial conditions and compare our numerical results to those obtained from
a time-independent Floquet theory in the large frequency regime. Our work offers the possibility of engineering
and controlling unconventional pairing states in fermionic condensates.
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