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Transport in Floquet-Bloch bands

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 نشر من قبل C. J. Fujiwara
 تاريخ النشر 2018
  مجال البحث فيزياء
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We report Floquet band engineering of long-range transport and direct imaging of Floquet-Bloch bands in an amplitude-modulated optical lattice. In one variety of Floquet-Bloch band we observe tunable rapid long-range high-fidelity transport of a Bose condensate across thousands of lattice sites. Quenching into an opposite-parity Floquet-hybridized band allows Wannier-Stark localization to be controllably turned on and off using modulation. A central result of this work is the use of transport dynamics to demonstrate direct imaging of a Floquet-Bloch band structure. These results demonstrate that transport in dynamical Floquet-Bloch bands can be mapped to transport in quasi-static effective bands, opening a path to cold atom quantum emulation of ultrafast multi-band electronic dynamics.



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