Dai Hong-Yi

Classical Communication Cost and Remote Preparation of Multi-qubit with Three-Party

We present a scheme for probabilistic remote preparation of multi-qubit with three-party from a sender to either of two receivers. The quantum channel is composed of a partial entangled tripartite GHZ state. We obtain the successful total probability of the scheme in the general case and special case, respectively. We also calculate total classical communication cost required in the RSP process with three-party in the general case and special case, respectively.

Remote preparation of an entangled two-qubit state with three parties

We present a scheme for probabilistic remote preparation of an entangled two-qubit state with three parties from a sender to either of two receivers. The quantum channel is composed of a partially entangled two-qubit state and a partially entangled three-qubit state. We calculate the successful total probabilities of the scheme in general and particular cases, respectively. We also calculate total classical communication cost in a general case and two particular cases, respectively.

Probabilistic Remote Preparation of a Four-Particle Entangled W State for the General Case and for All Kinds of the Special Cases ∗

We present a protocol for probabilistic remote preparation of a four-particle entangled W state. The quantum channel is composed of two partial entangled four-particle cluster states. We calculate the total successful probability and total classical communication cost required for the general case and for all kinds of the special cases, respectively. It is shown that for two maximally entangled four-particle cluster states, such a scheme for the general case has the total successful probability of 25% and only consumes the total classical communication of 1 bit, while this scheme for the special cases under certain conditions can possess successful probability of 50% or 100%, the required classical communication will only be 2 bits or 4 bits. Meantime, we give in detail all unitary transformations for the general case and for all kinds of the special cases, respectively.

A New Scheme for Probabilistic Teleportation and Its Potential Applications

We propose a novel scheme to probabilistically teleport an unknown two-level quantum state when the information of the partially entangled state is only available for the sender. This is in contrast with the fact that the receiver must know the non-maximally entangled state in previous typical schemes for the teleportation. Additionally, we illustrate two potential applications of the novel scheme for probabilistic teleportation from a sender to a receiver with the help of an assistant, who plays distinct roles under different communication conditions, and our results show that the novel proposal could improve the security and enlarge the applied range of probabilistic teleportation. PACS numbers: 03.67.Hk, 03.67.-a, 03.65.-wWe propose a novel scheme to probabilistically teleport an unknown two-level quantum state when the information of the partially entangled state is only available for the sender. This is in contrast with the fact that the receiver must know the non-maximally entangled state in previous typical schemes for the teleportation. Additionally, we illustrate two potential applications of the novel scheme for probabilistic teleportation from a sender to a receiver with the help of an assistant, who plays distinct roles under different communication conditions, and our results show that the novel proposal could enlarge the applied range of probabilistic teleportation.

Teleportation of Three-Level Multi-partite Entangled State by a Partial Three-Level Bipartite Entangled State

We present a scheme for probabilistically teleporting an unknown three-level bipartite entangled state by using a partial entangled three-level bipartite state as quantum channel. This scheme can be directly generalized to probabilistically teleport an unknown three-level k-particle entangled state by a partial three-level bipartite entangled state. All kinds of unitary transformations are given in detail. We calculate the successful total probability and the total classical communication cost required for this scheme.

Probabilistic teleportation of the three-particle entangled state by the partial three-particle entangled state and the three-particle entangled W state

We present a scheme to teleport an unknown three-particle entangled state from a sender to either one of two receivers. The partial three-particle entangled state and the three-particle entangled W state are considered as the quantum channels. An unknown three-particle entangled state can be perfectly teleported probabilistically by performing two generalized Bell measurements and the Hadamard operation at the senders side and introducing an appropriate unitary transformation in each receivers laboratory conditioned on the simple measurement outcome of the other. All kinds of unitary transformations are given in details. This scheme can be directly generalized to teleport an unknown three-particle entangled state from a sender to any one of N receivers by the partial three-particle entangled state and the (N + 1)-particle entangled W state.

Decoy State Quantum Key Distribution with Odd Coherent State

We propose a decoy state quantum key distribution scheme with odd coherent state which follows sub-Poissonian distributed photon count and has low probability of the multi-photon event and vacuum event in each pulse. The numerical calculations show that our scheme can improve efficiently the key generation rate and secure communication distance. Furthermore, only one decoy state is necessary to approach to the perfect asymptotic limit with infinite decoy states in our scheme, but at least two decoy states are needed in other scheme.

Quantum Information Transfer in Circuit QED with Landau—Zener Tunneling

We propose a scheme to implement quantum information transfer between Cooper-pair boxes (CPBs) in a circuit quantum electrodynamic (QED) system with Landau—Zener tunneling. The system consists of two CPB qubits and a one-dimensional transmission line resonator (TLR). By analytically solving the eigenequation and numerically calculating the transition probability, the results show the quantum state transfer from one qubit to another via a fast adiabatic passage. The coupling mechanism is robust against decoherence effects.

Quantum phase transition of light in a one-dimensional photon-hopping-controllable resonator array

We give a concrete experimental scheme for engineering the insulator-superfluid transition of light in a one-dimensional (1-D) array of coupled superconducting stripline resonators. In our proposed architecture, the on-site interaction and the photon hopping rate can be tuned independently by adjusting the transition frequencies of the charge qubits inside the resonators and at the resonator junctions, respectively, which permits us to systematically study the quantum phase transition of light in a complete parameter space. By combining the techniques of photon-number-dependent qubit transition and fast read-out of the qubit state using a separate low-Q resonator mode, the statistical property of the excitations in each resonator can be obtained with a high efficiency. An analysis of the various decoherence sources and disorders shows that our scheme can serve as a guide to coming experiments involving a small number of coupled resonators.

Signal-to-noise ratio of lensless ghost interference with thermal incoherent light＊

Factors in∞uencing the signal-to-noise ratio (SNR) of lensless ghost interference with thermal incoherent light are investigated. Our result shows that the SNR of lensless ghost interference is related to the transverse length of the object, the position of the object in the imaging system and the transverse size of the light source. Furthermore, the efiects of these factors on the SNR are discussed in detail by numerical simulations.