The ultrafine entanglement witness introduced by Shahandeh et al. [Phys. Rev. Lett. 118, 110502 (2017)] can seamlessly and easily improve any standard entanglement witness. In this paper, by combining the constraint and the test operators, we rotate the hyperplane determined by the test operator and further improve the original ultrafine entanglement witness. In particular, we present a series of ultrafine entanglement witnesses that not only can detect entangled states that the original ultrafine entanglement witnesses cannot detect, but also have the merits that the original ultrafine entanglement witnesses have.

• Received 22 December 2017

DOI:https://doi.org/10.1103/PhysRevA.97.032343