论文标题
晶格浮子系统中的非分散波数据包
Non-dispersing wave packets in lattice Floquet systems
论文作者
论文摘要
我们表明，在一维翻译不变的紧密结合链中，通常可以使用空间上的不均匀驱动器将非分散的波数据包实现为floquet特征态或线性组合，或者是线性组合的，这可以像单个位点上的调制一样简单。这些波数据包（它们的“往返时间”时间）的复发时间以合理比率$ st/r $的驱动期$ t $的锁定，其中$ s，r $是联合总体整数。不同$ s/r $的波数据包可以在同一驱动器下共存，但以不同的速度行驶。他们保留无限的空间紧凑度（$ s/r = 1 $）或长时间（$ s/r \ neq 1 $）。离散的时间翻译对称性显然因$ s \ neq 1 $而打破，让人联想到floquet时间晶体。我们进一步演示了如何反向工程驱动方案来重现目标浮子微型电位，例如波数据包的自由传播，就好像来自严格的线性能量谱。各种控制方案为量子信息科学领域的浮雕工程开辟了新的途径。
We show that in a one-dimensional translationally invariant tight binding chain, non-dispersing wave packets can in general be realized as Floquet eigenstates -- or linear combinations thereof -- using a spatially inhomogeneous drive, which can be as simple as modulation on a single site. The recurrence time of these wave packets (their "round trip" time) locks in at rational ratios $sT/r$ of the driving period $T$, where $s,r$ are co-prime integers. Wave packets of different $s/r$ can co-exist under the same drive, yet travel at different speeds. They retain their spatial compactness either infinitely ($s/r=1$) or over long time ($s/r \neq 1$). Discrete time translation symmetry is manifestly broken for $s \neq 1$, reminiscent of Floquet time crystals. We further demonstrate how to reverse-engineer a drive protocol to reproduce a target Floquet micromotion, such as the free propagation of a wave packet, as if coming from a strictly linear energy spectrum. The variety of control schemes open up a new avenue for Floquet engineering in quantum information sciences.
