AI 中文总结
该研究提出用自由电子作为量子写入器，通过匹配波矢与包络，可高保真制备原子阵列的最亚辐射态，还能激发平行原子链的强亚辐射反对称态。
AI 中文摘要
自由空间中有限亚波长原子链的最亚辐射本征态受强抑制的辐射衰变保护，是光子存储、量子传感和多体量子光学的强大资源。然而其光学制备受限于需同时匹配光锥外的波矢与非均匀包络。本文证明自由电子可克服这些约束：其速度设定印记波矢，衍射波包的轨迹塑造激发包络。这种动量与包络的同时匹配可实现 heralded 制备，在传播自由空间光子难以企及的深亚波长区域，条件保真度接近1（F>99.5%）。进一步研究表明，路径叠加的自由电子可激发两条紧密平行链中的反对称态，链间相消干涉产生的亚辐射性强于相同总原子数的单链。这些结果确立自由电子作为量子写入器，可制备传播光场难以获取的集体激发。
英文摘要
The most subradiant eigenstate of a finite subwavelength atomic chain in free space, protected by strongly suppressed radiative decay, offers a powerful resource for photon storage, quantum sensing, and many-body quantum optics. Yet its optical preparation is hindered by the simultaneous need to match a wave vector outside the light cone and a nonuniform envelope. Here, we show that a free electron can overcome these constraints: its velocity sets the imprinted wave vector, while the trajectory of the diffracting wave packet shapes the excitation envelope. This simultaneous momentum and envelope matching enables heralded preparation with near-unity conditional fidelity ($F>99.5\%$) even in a deeply subwavelength regime that is difficult to access with propagating free-space photons. We further show that a path-superposed free electron can excite an antisymmetric state in two closely spaced parallel chains, whose interchain destructive interference yields stronger subradiance than a single chain with the same total number of atoms. These results establish free electrons as quantum writers for collective excitations that are difficult to access with propagating optical fields.
Comments6-page main text with 4 figures; 15-page Supplemental Material with 2 figures and 2 tables
