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The quantum no-cloning theorem and no-deleting theorem may be the most important quantum features for quantum communications or quantum computations. In this paper, we concentrate typical properties of random quantum evolution. We obtain that universal random evolutions change the generic unknown pure states into their orthogonal states approximately. Moreover, typical random evolutions distort the von Neumann entropy with constants. These results are extended to mixed states with a stronger orthogonal preparation ability. These typical characters are very important for quantum information retrieving or various quantum tasks. [ABSTRACT FROM AUTHOR]

In this paper, several new protocols for the controlled remote state preparation (CRSP) by using the Brown state as the quantum channel are proposed. Firstly, we propose a CRSP protocol of an arbitrary two qubit state. Then, the CRSP protocol of an arbitrary three qubit state, which has rarely been considered by the previous papers, is investigated. The coefficients of the prepared states can be not only real, but also complex. To design these protocols, some useful and general measurement bases are constructed, which can greatly reduce the restrictions for the coefficients of the prepared states. The security analysis is provided in detail. Moreover, receiver's all recovery operations are summarized into a concise formula. [ABSTRACT FROM AUTHOR]