On the optimal certification of von Neumann measurements

Certification and validation of sources producing quantum states and measurement devices are a necessary step of quantum technology. Certification of quantum measurements is entwined with quantum hypotheses testing, however, we are allowed to prepare an input state and the final measurement. In this report, we begin with studying the two-point certification of pure quantum states and unitary channels to later use them to prove our main result, which is the certification of von Neumann measurements in single-shot and parallel scenarios. In particular, in all the above-mentioned scenarios we characterize the optimal probability of the type II error given some fixed statistical significance. We also state the conditions when two quantum objects cannot be distinguished perfectly but still can be certified. Moreover, we show the connection between the certification of quantum channels and the notion of q-numerical range.