利用受激参量下转换对空间纠缠进行无符合认证和量化
Coincidence free certification and quantification of spatial entanglement with stimulated parametric down conversion
AI总结：
研究利用受激参量下转换，通过用经典光束注入信号模式并测量受激闲频场，以强度测量取代双光子符合计数来认证空间纠缠，可用于困难耗时条件下光子对源纠缠特性研究。
AI中文摘要：
通过受激发射，光子对源可通过用明亮经典光束注入信号模式并测量受激闲频场来表征，从而用经典强度检测取代双光子符合计数。我们将此方法应用于下转换源的连续横向空间自由度，并表明仅通过强度测量就可以认证空间纠缠。我们通过基于方差的纠缠和导引见证以及费多罗夫比率证明了这种能力。该方法对于在对准和光子计数测量困难且耗时的条件下研究光子对源的纠缠特性很有用。
英文摘要：
Using stimulated emission, a photon pair source can be characterized by seeding the signal mode with a bright classical beam and measuring the stimulated idler field, thus replacing two-photon coincidence counting with classical intensity detection. We apply this approach to the continuous transverse spatial degrees of freedom of a down conversion source and show that it is possible to certify spatial entanglement with only intensity measurements. We demonstrate this capability through variance-based entanglement and steering witnesses, as well as the Fedorov ratio. This method is useful for studying entanglement properties of photon pair sources in conditions where alignment and photon counting measurements are difficult and time-consuming.
