Exploring Bell inequalities for the device-independent certification of entanglement depth

Pei-Sheng Lin^1*, Jui-Chen Hung¹, Ching-Hsu Chen², Yeong-Cherng Liang¹

¹Department of Physics, National Cheng Kung Universtiy, Tainan, Taiwan
²Department of Electrophysics, National Chiayi University, Chiayi, Taiwan

* Presenter:Pei-Sheng Lin, email:pslin@phys.ncku.edu.tw

Techniques developed for device-independent characterizations allow one to certify certain physical properties of quantum systems without assuming any knowledge of their internal workings. Such a certification, however, often relies on the employment of device-independent witnesses catered for the particular state and property of interest. In this work, we consider some Bell inequalities involving two dichotomic observables per party and show that they are suited for the detection of genuine many-body entanglement, as well as the entanglement depth present in certain well-known multipartite quantum states, including (higher-dimensional generalizations of) the Greenberger-Horne-Zeilinger (GHZ) states, and certain families of graph states. The connection between a class of these inequalities with the so-called GHZ paradox and the robustness of these witnesses in the presence of white noise will be discussed.

Keywords: multipartite entanglement, entanglement depth, device-independent witness