Datensatz

Zusammenfassung

We present a compressive quantum process tomography scheme that fully
characterizes any rank-deficient completely-positive process with no a priori
information about the process apart from the dimension of the system on which
the process acts. It uses randomly-chosen input states and adaptive output von
Neumann measurements. Both entangled and tensor-product configurations are
flexibly employable in our scheme, the latter which naturally makes it
especially compatible with many-body quantum computing. Two main features of
this scheme are the certification protocol that verifies whether the
accumulated data uniquely characterize the quantum process, and a compressive
reconstruction method for the output states. We emulate multipartite scenarios
with high-order electromagnetic transverse modes and optical fibers to
positively demonstrate that, in terms of measurement resources, our
assumption-free compressive strategy can reconstruct quantum processes almost
equally efficiently using all types of input states and basis measurement
operations, operations, independent of whether or not they are factorizable
into tensor-product states.