It is a fundamental consequence of the superposition principle for quantum states that there
must exist nonorthogonal states, that is, states that, although different, have a nonzero …

In quantum information processing and quantum computing protocols the carrier of
information is a quantum system and information is encoded in the state of a quantum …

We report an experimental implementation of free-space quantum secure direct
communication based on single photons. The quantum communication scheme uses phase …

Quantum secure direct communications (QSDC) can directly transmit secret messages
through a quantum channel without keys. The imperfect photon source is a major obstacle …

The main purpose of this paper is to examine some (potential) applications of quantum
computation in AI and to review the interplay between quantum theory and AI. For the …

We address the problem of unambiguous discrimination among a given set of quantum
operations. The necessary and sufficient condition for them to be unambiguously …

A survey of various concepts in quantum information is given, with a main emphasis on the
distinguishability of quantum states and quantum correlations. Covered topics include …

We investigate generalized measurements, based on positive-operator-valued measures,
and von Neumann measurements for the unambiguous discrimination of two mixed …

Determining the state of a quantum system is a central task in quantum information
processing since it encompasses the read-out problem. Very often the optimized state …

The discrimination of quantum operations has long been an intriguing challenge, with
theoretical research notably advancing our understanding of the quantum features in …