Improving of steering and nonlocality via local filtering operation in Heisenberg XY model

Abstract

In this work, we mainly study quantum steering and nonlocality of two-qubit Heisenberg [Formula: see text] spin-1/2 chain via local filtering operation. Our analytical results show that quantum steering and nonlocality can be affected by coupling constant [Formula: see text], temperature [Formula: see text], external magnetic field [Formula: see text] and anisotropy constant [Formula: see text]. Quantum steering and nonlocality would degrade with the increase of temperature [Formula: see text] and anisotropy constant [Formula: see text]. When [Formula: see text] is small, we can observe quantum steering and nonlocality increase with [Formula: see text]. When [Formula: see text] getting bigger, what we will see is that steering goes down first, then grows up. We can improve quantum steering and nonlocality via local filtering operation. We chose an appropriate parameter [Formula: see text], the steering and nonlocality can be improved when we fix three in those four parameters. There is a queer phenomenon in some situations that the range of one side for steering and nonlocality can extend greatly by losing them in another side. Therefore, our investigations might shed light on steering and nonlocality under the Heisenberg [Formula: see text] spin chain model and make a little step in the progress of quantum information.