论文标题
在光滑且非平滑驱动的情况下，浮标多体局部阶段的稳健性
Robustness of the Floquet many-body localized phase in the presence of a smooth and a non-smooth drive
论文作者
论文摘要
在这项工作中，我们调查了Floquet MBL至erergodic相变的关键驾驶幅度如何在各种驱动频率上平滑和非平滑驾驶之间有所不同。为此，我们在数值上研究了一个无序的自旋1/2链，该链分别由正弦或方波驱动器分别驱动。在这两种情况下，临界驱动幅度都随频率单调增加，并且在很大的频率下，在适当的归一化中，这两个驱动器都是相同的。但是，在低和中间频率下，方波驱动的临界幅度很大取决于频率，而余弦驱动器之一在较大的频率范围内几乎是恒定的。通过在傅立叶空间透视上分析驱动诱导的共振的密度，我们得出结论，这种差异是由于在方波（Sine）驱动器的傅立叶光谱中存在的较高谐波引起的共振引起的。此外，我们建议一种基于测量驱动诱导的共振的密度，提出了一种数值有效的方法来估计不同驱动器的关键驱动振幅的频率依赖性。
In this work, we investigate how the critical driving amplitude at the Floquet MBL-to-ergodic phase transition differs between smooth and non-smooth driving over a wide range of driving frequencies. To this end, we study numerically a disordered spin-1/2 chain which is periodically driven by a sine or a square-wave drive, respectively. In both cases, the critical driving amplitude increases monotonically with the frequency, and at large frequencies, it is identical for the two drives in the appropriate normalization. However, at low and intermediate frequencies the critical amplitude of the square-wave drive depends strongly on the frequency, while the one of the cosine drive is almost constant in a wide frequency range. By analyzing the density of drive-induced resonance in a Fourier space perspective, we conclude that this difference is due to resonances induced by the higher harmonics which are present (absent) in the Fourier spectrum of the square-wave (sine) drive. Furthermore, we suggest a numerically efficient method to estimate the frequency dependence of the critical driving amplitudes for different drives, based on measuring the density of drive-induced resonances.
