  The Einstein-Podolsky-Rosen (EPR) steering is an intermediate quantum
nonlocality between entanglement and Bell nonlocality, which plays an important
role in quantum information processing tasks. In the past few years, the
investigations concerning EPR steering have been demonstrated in a series of
experiments. However, these studies rely on the relevant steering inequalities
and the choices of measurement settings. Here, we experimentally verify the EPR
steering via entanglement detection without using any steering inequality and
measurement setting. By constructing two new states from a two-qubit target
state, we observe the EPR steering by detecting the entanglement of these new
states. The results show that the entanglement of the newly constructed states
can be regarded as a new kind of steering witness for target states. Compared
to the results of Xiao et al. [Phys. Rev. Lett. 118, 140404 (2017)], we find
that the ability of detecting EPR steering in our scenario is stronger than
two-setting projective measurements, which can observe more steerable states.
Hence, our demonstrations can deepen the understanding of the connection
between the EPR steering and entanglement.
