AI 中文总结
该研究揭示量子光驱动强场电离时光电子纵向动量呈$I^{2/3}$标度的反常辐射压力，明确其源于场振幅鞍点结构，确立纵向动量转移为强场量子光学中编码光子统计与场相干性的独特可观测量。
AI 中文摘要
我们表明，在明亮压缩真空驱动的强场电离中，光电子的平均纵向动量随平均入射强度$I$的标度关系为$I^{2/3}$，而非相干光驱动下的线性关系。这种反常标度源于场振幅的鞍点结构：非线性隧穿从宽泛的量子涨落中选出两个大小相等、符号相反的主导场振幅。对最终光子态的追踪会抹去它们的相对相位信息，仅保留共同的大小，以决定与场相关的纵向动量偏移及其$I^{2/3}$标度。而光子数分辨则会保留这种相干性，通过两个相差半个周期的场路径之间的时域双缝干涉，产生与宇称相关的纵向动量转移调制。这些结果确立了纵向动量转移作为强场量子光学中一种独特的可观测物理量，可编码强光量子光的光子统计特性和场相干性。
英文摘要
We show that in strong-field ionization driven by bright squeezed vacuum, the mean longitudinal photoelectron momentum scales with the mean incident intensity $I$ as $I^{2/3}$, rather than linearly as under coherent-light driving. This anomalous scaling originates from a field-amplitude saddle-point structure: nonlinear tunneling selects two dominant field amplitudes of equal magnitude and opposite sign from the broad quantum fluctuations. Tracing over the final photon state erases their relative-phase information, leaving their common magnitude to determine the field-dependent longitudinal momentum shift and its $I^{2/3}$ scaling. Photon-number resolution instead preserves this coherence, producing parity-dependent modulations of the longitudinal momentum transfer through time-domain double-slit interference between two field pathways separated by half a cycle. These results establish longitudinal momentum transfer as a distinct observable in strong-field quantum optics that encodes both the photon statistics and the field coherence of intense quantum light.
Comments9 pages, 5 figures
