UNITARY CONTROL PROCESS FOR QUANTUM OPTIMUM DETECTION

摘要

It will be shown that the minimum error bound in binary decision of linearly-independent pure-state signals can be achieved for any given measurement process by installing an appropriate unitary transformation for the signal states in front of the measurement. The optimum decision problem can be viewed as how to find this transformation which modifies the received signals so as to cause the quantum interference optimally at the measurement. It will be discussed how the origin of the error reduction can be identified and how the required unitary control process can be constructed.