Prof. Daowen Qiu

Prof. Daowen Qiu

Sun Yat-sen University

Research Experience:

Prof. Daowen Qiu have published over 130 papers in peer-review journals, and over 25 conferences papers. More specifically, (1) we have systematically studied a number of different QFA (quantum finite automata) models, and solved the decidability of equivalence and minimization of these QFA models. Therefore, we have answered the problems of how to decide the equivalence of quantum sequential machines proposed by Professor Gudder, and how to decide the equivalence of MM-1QFA proposed by Professor Gruska. In particular, we have answered the problems of how to minimize QFAs proposed by Moore and Crutchfield. Also, we have studied some properties of 2QFAC, quantum pushdown automata, and quantum Turing machines. (2) We have proved the characterization of all Boolean functions that can be solved by quantum 1-query algorithm. (3) We have studied quantum states discrimination and quantum cloning machines, and we have derived some bounds on unambiguous discrimination and minimum-error discrimination (some bounds are optimal to a certain extent), and some relationships between unambiguous discrimination and minimum-error discrimination have been clarified. Also, we have established a generic machine model of probabilistic cloning and deleting, and proposed a universal probabilistic deleting machine. (4) We have studied quantum teleportation and superdence coding based on different entangled states (W-states). (5) We have studied semi-quantum cryptography and proved that a semi-quantum key distribution protocol is unconditional security. (6) We have discovered some essential connections between quantum logic and models of computation, and we have established residuated lattice-valued automata theory. (6) We have established a fundamental framework of the supervisory control for fuzzy discrete event systems (FDES).