Teleportation Scheme Research Articles

Improving the Teleportation Scheme of Five-Qubit State with a Seven-Qubit Quantum Channel

Recently, Min Li et al. (Int. J. Theor. Phys. 56, 2710, 2017) proposed an improved quantum teleportation scheme for one five-qubit unknown state with a seven-qubit quantum channel. In this paper, we present an improved protocol with only single-qubit measurements and the same seven-qubit quantum channel. Compared with previous scheme proposed, our scheme has obvious advantages of requiring fewer classical resources, possessing higher intrinsic efficiency and lower operation complexity that bring a better flexibility.

Continuous-variable quantum teleportation through bosonic memory channel

We put forward a scheme for quantum teleportation of continuous-variable Gaussian states using, as a quantum channel, a two-mode squeezed vacuum interacting with a thermal environment showing memory effects. We found that fidelity larger than the classical limit may be obtained, upon exploiting memory effects, also using lower measurement gain. We show that fidelity increases with the memory of the channel and decreases with the thermal noise. Finally, we discuss the effects of memory on the distortion cumulants.

Quantum Controlled Teleportation of Arbitrary Two-Qubit State via Entangled States

We put forward an efficient quantum controlled teleportation scheme, in which arbitrary two-qubit state is transmitted from the sender to the remote receiver via two entangled states under the control of the supervisor. In this paper, we use the combination of one two-qubit entangled state and one three-qubit entangled state as quantum channel for achieving the transmission of unknown quantum states. We present the concrete implementation processes of this scheme. Furthermore, we calculate the successful probability and the amount of classical information of our protocol.

Multi-hop teleportation in a quantum network based on mesh topology

In this paper, we propose a mesh-topology-based multi-hop teleportation scheme for a quantum network. By using the proposed scheme, quantum communication can be realized between two arbitrary nodes, even when they do not share a direct quantum channel. Einstein–Podolsky–Rosen pairs are used as quantum channels. The source node (initial sender) and all intermediate nodes make Bell measurements independently. They send the results to the destination node (final receiver) by classical channels. The quantum state can be determined from the Bell measurement result, and only the destination node is required for simple unitary transformation. This method of simultaneous measurement contributes significantly to quantum network by reducing the hop-by-hop transmission delay.

Efficient schemes for the quantum teleportation of a sub-class of tripartite entangled states

In this paper we propose two schemes for teleportation of a sub-class of tripartite states, the first one with the four-qubit cluster state and the second one with two Bell pairs as entanglement channels. A four-qubit joint measurement in the first case and two Bell measurements in the second are performed by the sender. Appropriate unitary operations on the qubits at the receiver's end along with an ancilla qubit result in the perfect teleportation of the tripartite state. Analysis of the quantum circuits employed in these schemes reveal that in our technique the desired quantum tasks are achieved with lesser quantum cost, gate count and classical communication bits compared with other similar schemes.

A perfect multi-hop teleportation scheme for transfer of five-qubit entangled states using intermediate nodes

In this paper, we consider a multi-hop teleportation protocol for transfer of certain five-qubit entangled states. The speciality of this protocol is that intermediate nodes between the sender and the receiver are introduced. Teleportation processes over long distances are problematic because of the existence of the environmental noise which is almost unavoidable and adversely affects the entangled quantum channel. With a view to the above, intermediate nodes are introduced which are connected in series by entanglement. These short range quantum channels minimize the risk of the protocol being affected by noise. The present protocol is performed in an integrated manner in which the parties in the intermediate nodes act independently. A remarkable feature of the protocol is that only 3.13% of the basis elements are involved in the measurements. We also calculate the efficiency and indicate the advantages of the present protocol. The work is in the direction of research for transferring entangled quantum states.

Bidirectional Controlled Quantum Teleportation in the Three-dimension System

We present a scheme for bidirectional controlled quantum teleportation (BCQT) via a five-qutrit entangled state as the quantum channel. In this scheme, two distant parties, Alice and Bob, are not only senders but also receivers, and Alice wants to teleport an unknown single-qutrit state to Bob, at the same time, Bob wishes to teleport another arbitrary single-qutrit state, respectively. It is shown that, only if the two senders and the controller collaborate with each other, the BCQT can be completed successfully.

Comment on “Quantum Teleportation of Eight-Qubit State via Six-Qubit Cluster State”

Recently, Zhao et al., (Int. J. Theor. Phys. 57, 516-522 (2018)) have proposed a scheme for quantum teleportation of an eight-qubit quantum state using a six qubit cluster state. In this comment, it's shown that the quantum resource (multi-partite entangled state used as the quantum channel) used by Zhao et al., is excessively high and the task can be performed using any two Bell states as the task can be reduced to the teleportation of an arbitrary two qubit state. Further, a trivial conceptual mistake made by Zhao et al., in the description of the quantum channel has been pointed out. It's also mentioned that recently a trend of proposing teleportation schemes with excessively high quantum resources has been observed and the essence of this comment is applicable to all such proposals.

Probabilistic teleportation via multi-parameter measurements and partially entangled states

In this paper, a novel scheme for probabilistic teleportation is presented with multi-parameter measurements via a non-maximally entangled state. This is in contrast to the fact that the measurement kinds for quantum teleportation are usually particular in most previous schemes. The detail implementation producers for our proposal are given by using of appropriate local unitary operations. Moreover, the total success probability and classical information of this proposal are calculated. It is demonstrated that the success probability and classical cost would be changed with the multi-measurement parameters and the entanglement factor of quantum channel. Our scheme could enlarge the research range of probabilistic teleportation.

A simplified formalism of the algebra of partially transposed permutation operators with applications

Herein we continue the study of the representation theory of the algebra of permutation operators acting on the -fold tensor product space, partially transposed on the last subsystem. We develop the concept of partially reduced irreducible representations, which allows us to significantly simplify previously proved theorems and, most importantly, derive new results for irreducible representations of the mentioned algebra. In our analysis we are able to reduce the complexity of the central expressions by getting rid of sums over all permutations from the symmetric group, obtaining equations which are much more handy in practical applications. We also find relatively simple matrix representations for the generators of the underlying algebra. The obtained simplifications and developments are applied to derive the characteristics of a deterministic port-based teleportation scheme written purely in terms of irreducible representations of the studied algebra. We solve an eigenproblem for the generators of the algebra, which is the first step towards a hybrid port-based teleportation scheme and gives us new proofs of the asymptotic behaviour of teleportation fidelity. We also show a connection between the density operator characterising port-based teleportation and a particular matrix composed of an irreducible representation of the symmetric group, which encodes properties of the investigated algebra.

Enhancement of quantum Fisher information of quantum teleportation by optimizing partial measurements

The purpose of quantum teleportation is to achieve perfect transmission of quantum information from one site to another distant site. In the teleportation process, the quantum system is inevitably affected by its surrounding environment, causing the system to lose its coherence, which will result in distortion of the transmitted information. In recent years, weak measurement and measurement reversal have been proposed to suppress the decoherence of quantum entanglement and protect some quantum states. On the other hand, quantum Fisher information (QFI) is an important physical quantity in quantum metrology, which can give the optimal value estimating the accuracy of parameters. As is well known, QFI is highly susceptible to environmental noise and can lead its measurement accuracy to decrease. Therefore, it is of great importance to examine how to protect QFI from being influenced by the external circumstance during the teleportation procedure. In this paper, we study how to improve the QFI of teleporting a single-qubit state via a Greenberger-Horne-Zeilinger state in a finite temperature environment with the technique of weak measurement and weak measurement reversal. According to different qubit transmission cases of three quantum teleportation schemes, we consider their respective QFIs in detail. After constructing the quantum logic circuit of each teleportation scheme, we first analyze the variance trend of QFI against the generalized amplitude damping noise parameters. Then by introducing weak measurement and measurement reversal on each noise particle of the three schemes, we optimize the related partial measurement parameters and explore the corresponding improved QFI, namely, the difference between the QFI with optimal partial measurements and that without partial measurements. We find that optimizing partial measurements can efficiently enhance the QFI of the teleported state for the three kinds of teleportation schemes at finite temperature. Moreover, with the value of p fixed, the lower the environment temperature, the larger the value of the improved QFI is. Our results could be useful in further understanding the applications of weak measurement and measurement reversal to the quantum communication process and may shed light on estimating some relevant quantum parameters and implementing quantum information tasks.

A Novel Scheme for Bidirectional and Hybrid Quantum Information Transmission via a Seven-Qubit State

In this paper, we present a novel scheme for bidirectional and hybrid quantum information transmission via a seven-qubit state. We demonstrate that under the control of the supervisor two distant participants can simultaneously and deterministically exchange their states with each other no matter whether they know the states or not. In our scheme, Alice can teleport an arbitrary single-qubit state (two-qubit state) to Bob and Bob can prepare a known two-qubit state (single-qubit state) for Alice simultaneously via the control of the supervisor Charlie. Compared with previous studies for single bidirectional quantum teleportation or single bidirectional remote state preparation schemes, our protocol is a kind of hybrid approach for quantum information transmission. Furthermore, it achieves success with unit probability. Notably, since only pauli operations and two-qubit and single-qubit measurements are used in our schemes, it is flexible in physical experiments.

Implementation of controlled quantum teleportation with an arbitrator for secure quantum channels via quantum dots inside optical cavities

We propose a controlled quantum teleportation scheme to teleport an unknown state based on the interactions between flying photons and quantum dots (QDs) confined within single- and double-sided cavities. In our scheme, users (Alice and Bob) can teleport the unknown state through a secure entanglement channel under the control and distribution of an arbitrator (Trent). For construction of the entanglement channel, Trent utilizes the interactions between two photons and the QD-cavity system, which consists of a charged QD (negatively charged exciton) inside a single-sided cavity. Subsequently, Alice can teleport the unknown state of the electron spin in a QD inside a double-sided cavity to Bob’s electron spin in a QD inside a single-sided cavity assisted by the channel information from Trent. Furthermore, our scheme using QD-cavity systems is feasible with high fidelity, and can be experimentally realized with current technologies.

Design and experimental realization of an optimal scheme for teleportation of an n-qubit quantum state

An explicit scheme (quantum circuit) is designed for the teleportation of an $n$-qubit quantum state. It is established that the proposed scheme requires an optimal amount of quantum resources, whereas larger amount of quantum resources has been used in a large number of recently reported teleportation schemes for the quantum states which can be viewed as special cases of the general $n$-qubit state considered here. A trade off between our knowledge about the quantum state to be teleported and the amount of quantum resources required for the same is observed. A proof of principle experimental realization of the proposed scheme (for a 2-qubit state) is also performed using 5-qubit superconductivity-based IBM quantum computer. Experimental results show that the state has been teleported with high fidelity. Relevance of the proposed teleportation scheme has also been discussed in the context of controlled, bidirectional, and bidirectional-controlled state teleportation.

Improving the Teleportation Scheme of Three-Qubit State with a Four-Qubit Quantum Channel

Recently, Zhao-Hui Wei et al. (Int. J. Theor. Phys. 55, 4687, 2016) proposed an improved quantum teleportation scheme for one three-qubit unknown state with a four-qubit quantum channel based on the original one proposed by Binayak S. Choudhury and Arpan Dhara (Int. J. Theor. Phys. 55, 3393, 2016). According to their schemes, the three-qubit entangled state could be teleported with one four-qubit cluster state and five-qubit joint measurements or four-qubit joint measurements. In this paper, we present an improved protocol only with single-qubit measurements and the same four-qubit quantum channel, lessening the difficulty and intensity of necessary operations.

Quantum Communication Using Coherent Rejection Sampling.

Compression of a message up to the information it carries is key to many tasks involved in classical and quantum information theory. Schumacher [B. Schumacher, Phys. Rev. A 51, 2738 (1995)PLRAAN1050-294710.1103/PhysRevA.51.2738] provided one of the first quantum compression schemes and several more general schemes have been developed ever since [M. Horodecki, J. Oppenheim, and A. Winter, Commun. Math. Phys. 269, 107 (2007); CMPHAY0010-361610.1007/s00220-006-0118-xI. Devetak and J.Yard, Phys. Rev. Lett. 100, 230501 (2008); PRLTAO0031-900710.1103/PhysRevLett.100.230501A. Abeyesinghe, I. Devetak, P. Hayden, and A. Winter, Proc.R. Soc. A 465, 2537 (2009)PRLAAZ1364-502110.1098/rspa.2009.0202]. However, the one-shot characterization of these quantum tasks is still under development, and often lacks a direct connection with analogous classical tasks. Here we show a new technique for the compression of quantum messages with the aid of entanglement. We devise a new tool that we call the convex split lemma, which is a coherent quantum analogue of the widely used rejection sampling procedure in classical communication protocols. As a consequence, we exhibit new explicit protocols with tight communication cost for quantum state merging, quantum state splitting, and quantum state redistribution (up to a certain optimization in the latter case). We also present a port-based teleportation scheme which uses a fewer number of ports in the presence of information about input.

Port-based teleportation in arbitrary dimension

Port-based teleportation (PBT), introduced in 2008, is a type of quantum teleportation protocol which transmits the state to the receiver without requiring any corrections on the receiver’s side. Evaluating the performance of PBT was computationally intractable and previous attempts succeeded only with small systems. We study PBT protocols and fully characterize their performance for arbitrary dimensions and number of ports. We develop new mathematical tools to study the symmetries of the measurement operators that arise in these protocols and belong to the algebra of partially transposed permutation operators. First, we develop the representation theory of the mentioned algebra which provides an elegant way of understanding the properties of subsystems of a large system with general symmetries. In particular, we introduce the theory of the partially reduced irreducible representations which we use to obtain a simpler representation of the algebra of partially transposed permutation operators and thus explicitly determine the properties of any port-based teleportation scheme for fixed dimension in polynomial time.

Asymmetric Bidirectional 3 ⇔ 2 Qubit Teleportation Protocol Between Alice and Bob Via 9-qubit Cluster State

In this paper we present a protocol to perform the task of a bilateral exchange of entanglements between two parties in the case where one of the parties holds a three particle entangled state where the other party holds a two particle entangled state. The protocol is supervised by a controller. The quantum channel used here is a nine particle entangled state. The speciality of the protocol is that in all the involved measurements only a fraction of the possible measurement outcomes appear which substantially simplifies the protocol. Our scheme is a perfect teleportation scheme, that is, the mutual transfer of entangled states is performed with certainty.

Cyclic quantum teleportation

We propose a scheme of cyclic quantum teleportation for three unknown qubits using six-qubit maximally entangled state as the quantum channel. Suppose there are three observers Alice, Bob and Charl...

Generalized teleportation by quantum walks

We develop a generalized teleportation scheme based on quantum walks with two coins. For an unknown qubit state, we use two-step quantum walks on the line and quantum walks on the cycle with four vertices for teleportation. For any d-dimensional states, quantum walks on complete graphs and quantum walks on d-regular graphs can be used for implementing teleportation. Compared with existing d-dimensional states teleportation, prior entangled state is not required and the necessary maximal entanglement resource is generated by the first step of quantum walk. Moreover, two projective measurements with d elements are needed by quantum walks on the complete graph, rather than one joint measurement with $$d^2$$ basis states. Quantum walks have many applications in quantum computation and quantum simulations. This is the first scheme of realizing communicating protocol with quantum walks, thus opening wider applications.