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We propose a scheme of controlled teleportation of an arbitrary three-qubit state by using a five-qubit cluster state. In our scheme, the sender Alice performs five sets of single-qubit measurements and the controller Charlie needs only take a single-qubit measurement. The receiver Bob can reconstruct the arbitrary three-qubit state by performing the single-qubit unitary operations and a controlled-NOT operation if he obtains the help of the controller. We show that the efficiency in this scheme approaches 100% [ABSTRACT FROM AUTHOR]

We propose a scheme of controlled cyclic quantum teleportation of an arbitrary two-qubit entangled state by using a ten-qubit entangled state. In our scheme, Alice can teleport an arbitrary two-qubit entangled state to Bob, Bob can teleport an arbitrary two-qubit entangled state to Charlie and at the same time Charlie can teleport an arbitrary two-qubit entangled state to Alice with the help of the controller David. [ABSTRACT FROM AUTHOR]

We demonstrate that a seven-qubit entangled state can be used to realize the deterministic tripartite controlled teleportation by performing Bell-state measurements, where Alice wants to teleport an arbitrary single-qubit state of qubit a to Bob, Charlie wants to teleport an arbitrary single-qubit state of qubit b to David and at the same time Edison wants to teleport an arbitrary single-qubit state of qubit c to Ford via the control of the supervisor Tom. [ABSTRACT FROM AUTHOR]

We demonstrate that a five-ion cluster state can be used to realize the deterministic controlled teleportation of an arbitrary two-ion state in ion-trap systems. The scheme does not involve Bell-state measurement and is insensitive to both the initial motional state and heating. [ABSTRACT FROM AUTHOR]

We propose a protocol of asymmetric bidirectional controlled teleportation by using a seven-photon entangled state. In our protocol, Alice can teleport an arbitrary single-photon state to Bob and at the same time Bob can teleport an arbitrary two-photon state to Alice via the control of the supervisor Charlie. In addition, ones only carry out the Bell-state measurements and single-photon measurement. [ABSTRACT FROM AUTHOR]

A scheme is presented to implement bidirectional controlled quantum teleportation (QT) by using a five-qubit entangled state as a quantum channel, where Alice may transmit an arbitrary single qubit state called qubit A to Bob and at the same time, Bob may also transmit an arbitrary single qubit state called qubit B to Alice via the control of the supervisor Charlie. Based on our channel, we explicitly show how the bidirectional controlled QT protocol works. By using this bidirectional controlled teleportation, espcially, a bidirectional controlled quantum secure direct communication (QSDC) protocol, i.e., the so-called controlled quantum dialogue, is further investigated. Under the situation of insuring the security of the quantum channel, Alice (Bob) encodes a secret message directly on a sequence of qubit states and transmits them to Bob (Alice) supervised by Charlie. Especially, the qubits carrying the secret message do not need to be transmitted in quantum channel. At last, we show this QSDC scheme may be determinate and secure. [ABSTRACT FROM AUTHOR]

We demonstrate that a six-atom cluster state can be used to realize the deterministic quantum state sharing of an arbitrary two-atom state in cavity QED. The scheme does not involve Bell-state measurement and is insensitive to both the cavity decay and the thermal field. In our scheme, any one of the two agents is sufficient to reconstruct the original state under the condition that he/she obtains the help of the other one, but only one of them cannot. [ABSTRACT FROM AUTHOR]

new scheme for controlled teleportation of an entangled coherent state (ECS) with the help of a four-mode cluster-type entangled coherent state (CTECS) is proposed in detail. In this scheme, a four-mode CTECS is shared by a sender, a controller and a receiver. At first, the sender performs photon number measurement on the modes at hand, and the controller also performs photon number measurement on his modes. Then the receiver can reconstruct the ECS by performing an appropriate unitary transformation on his mode after he knows the measured results of the sender and the controller. And the probability of successful controlled teleportation is approaching 1/2. [ABSTRACT FROM AUTHOR]

We propose a scheme for splitting an arbitrary two-qubit state among three parties by using a six-qubit cluster-class state as a quantum channel. Based on two Bell-state measurements (BSMs) and a two-qubit projective measurement, any one of the two agents can reconstruct the original state if he/she collaborates with the other one, whilst individual agent obtains no information. [ABSTRACT FROM AUTHOR]

We demonstrate that a genuine six-qubit entangled state introduced by Tapiador et al. [J. Phys. A42 (2009) 415301] can be used to realize the deterministic controlled teleportation of an arbitrary three-qubit state by performing only the Bell-state measurements. [ABSTRACT FROM AUTHOR]

new application of the genuinely entangled six-qubit state introduced recently by Borras et al. [J. Phys. A 40:13407, ] is investigated for the controlled teleportation of an arbitrary three-qubit state. In our scheme, a genuinely entangled six-qubit state and a Bell-state are shared by a sender (Alice), a controller (Charlie) and a receiver (Bob). Both the sender and the controller only need to perform Bell-state measurements (BSMs), the receiver can reconstruct the arbitrary three-qubit state by performing some appropriate unitary transformations on his qubits after he knows the measured results of both the sender and the controller. This controlled teleportation scheme is deterministic. [ABSTRACT FROM AUTHOR]