Modification of Quantum Measurements by Mapping onto Quantum States and Classical Outcomes
Dmitry Anatolevich Kronberg · Lobachevskii Journal of Mathematics · 2022
Abstract We consider a quantum-classical (q-c) channel associated with quantum observable and a function on the set of results which defines a subordinate observable. We describe this situation as a combination of two quantum channels, where the output of the first channel is the classical outcome of the subordinate observable and quantum state which can be measured to yield the measurement result of the original channel. We also show that, under certain conditions, the states after the first channel in the given decomposition provide better quantum properties than the classical output of the original q-c channel.