论文标题
多体系统中的量子绝热性和互补子空间中的几乎正交性
Quantum adiabaticity in many-body systems and almost-orthogonality in complementary subspace
论文作者
论文摘要
我们研究为什么在量子多体系统中，在许多情况下，绝热忠诚度和初始状态和瞬时基态之间的重叠几乎具有相同的值。我们详细介绍了如何通过多体系统的两个固有限制之间的相互作用来解释问题：进化参数的小值的极限和大型系统大小的极限。在前一种情况下，常规扰动理论提供了自然的解释。在后一种情况下，关键的观察结果是，位于初始状态的互补希尔伯特空间中的矢量对几乎是正交的。我们的一般发现通过驱动的水稻模型和驱动的相互作用的Kitaev链模型进行了说明，这是两个范式的多体系统的范式模型。
We study why in quantum many-body systems the adiabatic fidelity and the overlap between the initial state and instantaneous ground states have nearly the same values in many cases. We elaborate on how the problem may be explained by an interplay between the two intrinsic limits of many-body systems: the limit of small values of evolution parameter and the limit of large system size. In the former case, conventional perturbation theory provides a natural explanation. In the latter case, a crucial observation is that pairs of vectors lying in the complementary Hilbert space of the initial state are almost orthogonal. Our general findings are illustrated with a driven Rice-Mele model and a driven interacting Kitaev chain model, two paradigmatic models of driven many-body systems.
