Kenji Nakahira

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Recently, a capacity-achievable quantum collective decoding was proposed. The decoding appears optimal in the limit of an infinite number of signals. However, in the case of finite signals, the error performance is as yet unknown. In the present paper, we apply the idea of quantum collective decoding to the construction of a quantum receiver for M-ary(More)
We derive some properties of minimum-error measurements for mixed quantum state signals where a density operator itself has a certain symmetry. In the first case, we show that if there exists a regular normal operator that commutes with each density operator of mixed state signals, then there exists an optimal measurement that consists of detection(More)
A genetic algorithm has been applied to the line profile reconstruction from the signals of the standard secondary electron (SE) and/or backscattered electron detectors in a scanning electron microscope. This method solves the topographical surface reconstruction problem as one of combinatorial optimization. To extend this optimization approach for(More)
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