一維原子陣列中的穩態相和相互作用引發的激發耗竭

Abstract

光子晶體波導與原子陣列耦合的一維手性自旋網路構成了一種強耦合量子界面，在光子介導下產生的遠程偶極-偶極相互作用之下，該系統展現了許多引人入勝的量子集體動力學特徵。在本論文中，我們特別研究了具有兩種不同粒子間距的異質陣列在弱驅動場的條件下，由共振偶極-偶極相互作用及手性耦合相互競爭下所產生的原子激發穩態相。首先，我們確認了此驅動耗散系統的大部分穩態相是由均質陣列穩態相組合而成，而少部分的穩態相則出現了一些嶄新的激發分佈，揭示了連接異質陣列的界面原子的複雜行為。其次，在我們的模擬結果中，異質陣列在特定條件下將出現由相互作用引起的半耗竭激發現象，並且能夠以此製備 Bell 糾纏態或是 W 態。這在雙向耦合下的解析解中也得到了進一步的證實。除此之外，我們也進一步探索了系統動態演化下產生的激發反射與激發阻塞現象，由此解釋半耗竭相的生成。本研究結果為一維驅動-耗散系統所呈現原子激發量子相提供了洞察，同時也為量子資訊與量子計算中的奇特多體量子態模擬提供了基礎。

The coupling of a photonic crystal waveguide with an atomic array forms a one-dimensional chiral spin network that constitutes a strongly coupled quantum interface, exhibiting numerous fascinating quantum collective dynamics under the long-range dipole-dipole interactions mediated by photons. In this thesis, we particularly explore the atomic excitation steady states in a dissimilar array with two different interparticle spacings under weak driving felds, infuenced by the competition between the resonant dipole-dipole interaction and directionality of the chiral coupling. We identify that the majority of the steady states in a dissimilar array are combinations of steady states in a homogeneous array, while a minority of the states exhibit some novel excitation distributions, revealing the complex behaviors of the interface atom connecting dissimilar arrays. Furthermore, our simulations indicate the emergence of half-depletion excitations in a dissimilar array under specifc conditions, which allows for the preparation of Bell entangled states or W states. This is also corroborated by analytical solutions under bidirectional coupling. Additionally, we delve into the excitation refection and excitation blockade during the evolution of the system, elucidating the generation of half-depletion phases. Our fndings offer insights into the quantum phases of atomic excitations in one-dimensional driven-dissipative systems and lay the groundwork for simulating exotic many-body quantum states in quantum information and computation.