All Pure Bipartite Entangled States can be Self-Tested

TL;DR

This paper proves that all pure bipartite entangled states can be uniquely identified through device-independent self-testing, using specific correlations as their classical fingerprints, under minimal assumptions.

Contribution

It provides explicit self-testing correlations for every pure bipartite entangled state, affirmatively answering a longstanding open question.

Findings

All pure bipartite entangled states can be self-tested.

Explicit correlations are constructed for each state.

Self-testing is achieved under no-signaling and quantum mechanics assumptions.

Abstract

Device-independent self-testing allows to uniquely characterize the quantum state shared by untrusted parties (up to local isometries) by simply inspecting their correlations, and requiring only minimal assumptions, namely a no-signaling constraint on the untrusted parties and the validity of quantum mechanics. The device-independent approach exploits the fact that certain non-local correlations can be uniquely achieved by measurements on a particular quantum state. We can think of these correlations as a "classical fingerprint" of the self-tested quantum state. In this work, we answer affirmatively the outstanding open question of whether all pure bipartite entangled states can be self-tested, by providing explicit self-testing correlations for each.