Nonclassicality of a single-mode state can be quantified by the entanglement (potential) the state creates at the output of a beam splitter. Thus, beam splitter transformation can be utilized for obtaining single-mode nonclassicality conditions (quantifications) from two-mode entanglement criteria (measures). Here, (i) we employ this relation to quantify the single-mode nonclassicality (SMNc) of a nonlinear crystal field generating second harmonic signals. (ii) We also manage to witness the SMNc of superradiant emission, a non-Gaussian state, in a Dicke phase transition. Entanglement potential, at the beam splitter output, is obtained in terms of measurable single-mode quantities. Thus, presence of a beam splitter in an experiment is not necessary. Employing the beam splitter method, one can also utilize hybrid entanglement criteria as SMNc conditions working well in different classes of single-mode states. (iii) We also work on essentials of the entanglement-SMNc relation: one ...

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测量单模系统的非经典性

单模状态的非经典性可以通过该状态在分束器输出处产生的纠缠（电势）来量化。因此，分束器变换可用于从双模纠缠标准（度量）获得单模非经典条件（量化）。在这里，（i）我们采用这种关系来量化产生二次谐波信号的非线性晶体场的单模非经典性（SMNc）。（ii）我们还设法在Dicke相变中目睹了超高辐射的SMNc，这是一种非高斯状态。分束器输出处的纠缠电势是根据可测量的单模量获得的。因此，实验中不需要分束器。使用分束器方法 人们还可以利用混合纠缠准则，因为SMNc条件在不同类别的单模状态下均能很好地工作。（iii）我们还致力于纠缠-SMNc关系的要点：一个...