A scheme is proposed for involving programmable quantum logic gates via teleportation,which is a unique technique in quantum mechanics.In our scheme,considering the inevitable decoherence caused by noisy environment,the quantum states are not maximally entangled.We show the implementation of single qubit quantum gates and controlled-NOT(C-NOT) gate,which are universal quantum gates.Hence,any quantum gate can be implemented by using teleportation withnon-maximally entangled states.Furthermore,two schemes in differet connections of universal gates are proposed and compared,and our results show the parallel connection outperforms the cascade connection.
The past decade or two has witnessed tremendous progress in theory and practice of quantum control technologies.Bridging different scientific disciplines ranging from fundamental particle physics to nanotechnology,the goal of quantum control has been to develop effective and efficient tools for common analysis and design,but more importantly would pave the way for future technological applications.This article briefly reviews basic quantum control theory from the perspective of modeling,analysis and design,as well as considers future research directions.
We present a scheme for probabilistic transformation of special quantum states assisted by auxiliary qubits.In our scheme,if quantum states can be rewritten in a particular form,it is possible to transform such states into other states using lowerdimensional unitary operations that can be more easily realized in physical experiments.Furthermore,as an important application,we propose a generalized scheme that helps construct faithful quantum channels via various probabilistic channels when considering the existence of nonmaximally-entangled states.
This paper presents an approach to deterministically teleport an arbitrary two-qubit state through a one-dimensional four-qubit cluster state serving as a probabilistic quantum channel. The channel is modu- lated in advance to avoid damage to the original states in this scheme, which is caused by the inevitable failure of constructing a channel between the sender and the receiver. The scheme is flexible because the channel can be modulated either by the sender or by the receiver, with the option of deciding whether the sender or the receiver modulates the channel, according to the distribution of the available particle re- sources. The efficiency can be improved by reusing previously discarded results that may lead to a faithful channel. The scheme can be uniformly performed, so the design process can be greatly simplified to realize a reliable deterministic teleportation. Finally, the scheme is extended to deterministic teleportation of an arbitrary n-qubit state in a generalized form.
We present a new scheme for investigating the usefulness of non-maximally entangled states for multi-party quantum state shar-ing in a simple and elegant manner.In our scheme,the sender,Alice shares n various probabilistic channels composed of non-maximally entangled states with n agents in a network.Our protocol involves only Bell-basis measurements,single qubit measurements,and a two-qubit unitary transformation operated by free optional agents.Our scheme is a more convenient realiza-tion because no other multipartite joint measurements are needed.Furthermore,in our scheme various probabilistic channels lessen the requirement for quantum channels,which makes it more practical for physical implementation.
