ScholarBank@NUShttps://scholarbank.nus.edu.sgThe DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material.Sun, 25 Sep 2022 18:51:19 GMT2022-09-25T18:51:19Z5071- Teleportation of a bipartite entangled coherent state via a four-partite cluster-type entangled statehttps://scholarbank.nus.edu.sg/handle/10635/98215Title: Teleportation of a bipartite entangled coherent state via a four-partite cluster-type entangled state
Authors: Chen, H.-N.; Liu, J.-M.
Abstract: We present an optical scheme to almost completely teleport a bipartite entangled coherent state using a four-partite cluster-type entangled coherent state as quantum channel. The scheme is based on optical elements such as beam splitters, phase shifters, and photon detectors. We also obtain the average fidelity of the teleportation process. It is shown that the average fidelity is quite close to unity if the mean photon number of the coherent state is not too small. © 2009 Chinese Physical Society and IOP Publishing Ltd.
Thu, 01 Jan 2009 00:00:00 GMThttps://scholarbank.nus.edu.sg/handle/10635/982152009-01-01T00:00:00Z
- Quantum discord of a three-qubit W-class state in noisy environmentshttps://scholarbank.nus.edu.sg/handle/10635/112495Title: Quantum discord of a three-qubit W-class state in noisy environments
Authors: Guo, H.; Liu, J.-M.; Zhang, C.-J.; Oh, C.H.
Abstract: We study the dynamics of the pairwise quantum discord (QD), classical correlation (CC), and entanglement of formation (EOF) for the three-qubit W-class state under the influence of various Markovian noises by analytically solving the master equation in the Lindblad form. Through numerical analysis, we find that EOF decreases asymptotically to zero with time for the dephasing noise, but it undergoes sudden death for the bit-flip noise, the isotropic noise, as well as the dissipative and noisy environments. Moreover, QD decays to zero in an asymptotical way for all the noises we investigated. Thus, when the W-class state {pipe}W〉 123 is subject to the above Markovian noises, QD is more robust than EOF against decoherence excluding the phase-flip noise, implying that QD is more useful than entanglement to characterize the quantum correlation. We also find a remarkable character for the CC in the presence of the phase-flip noise, i.e., CC displays the behavior of sudden transition and then keeps constant permanently, but the corresponding QD just exhibits a very small sudden change. Furthermore, we verify the monogamic relation between the pairwise QD and EOF of the W-class state. © Rinton Press.
Sun, 01 Jan 2012 00:00:00 GMThttps://scholarbank.nus.edu.sg/handle/10635/1124952012-01-01T00:00:00Z
- Optical rotation of heavy hole spins by non-Abelian geometrical meanshttps://scholarbank.nus.edu.sg/handle/10635/97453Title: Optical rotation of heavy hole spins by non-Abelian geometrical means
Authors: Sun, H.; Feng, X.-L.; Wu, C.; Liu, J.-M.; Gong, S.; Oh, C.H.
Abstract: A non-Abelian geometric method is proposed for rotating of heavy hole spins in a singly positive charged quantum dot in Voigt geometry. The key ingredient is the delay-dependent non-Abelian geometric phase, which is produced by the nonadiabatic transition between the two degenerate dark states. We demonstrate, by controlling the pump, the Stokes and the driving fields, that the rotations about y and z axes with arbitrary angles can be realized with high fidelity. Fast initialization and heavy hole-spin-state readout are also possible. © 2009 The American Physical Society.
Thu, 03 Dec 2009 00:00:00 GMThttps://scholarbank.nus.edu.sg/handle/10635/974532009-12-03T00:00:00Z
- Remote preparation of arbitrary two- and three-qubit stateshttps://scholarbank.nus.edu.sg/handle/10635/97802Title: Remote preparation of arbitrary two- and three-qubit states
Authors: Liu, J.-M.; Feng, X.-L.; Oh, C.H.
Abstract: We present a scheme for remotely preparing an arbitrary two-qubit pure state by using two bipartite partially entangled states as the quantum channel, the scheme is then generalized to the arbitrary three-qubit case. For the two cases of remote state preparation, we construct two different efficient projective measurement bases at sender's side and calculate the corresponding success probabilities. It is shown that remote preparation of the two-qubit or three-qubit state can be probabilistically achieved with unity fidelity. Moreover, for some special ensembles of the initial states, we find that the success probability of preparation can be increased to four times for two-qubit states and eight times for three-qubit states, and is equal to one in the case of the maximal entanglement resources. © 2009 Europhysics Letters Association.
Sat, 01 Aug 2009 00:00:00 GMThttps://scholarbank.nus.edu.sg/handle/10635/978022009-08-01T00:00:00Z
- Teleportation of a two-particle four-component squeezed vacuum state by linear optical elementshttps://scholarbank.nus.edu.sg/handle/10635/98216Title: Teleportation of a two-particle four-component squeezed vacuum state by linear optical elements
Authors: Chen, H.; Liu, J.
Abstract: We present a linear optical scheme for achieving a unity fidelity teleportation of a two-particle four-component squeezed vacuum state using two entangled squeezed vacuum states as quantum channel. The devices used are beam splitters and ideal photon detectors capable of distinguishing between odd and even photon numbers. Moreover, we also obtain the success probability of the teleportation scheme. © 2009 Chinese Optics Letters.
Fri, 01 May 2009 00:00:00 GMThttps://scholarbank.nus.edu.sg/handle/10635/982162009-05-01T00:00:00Z
- Remote state preparation via a GHZ-class state in noisy environmentshttps://scholarbank.nus.edu.sg/handle/10635/97803Title: Remote state preparation via a GHZ-class state in noisy environments
Authors: Liang, H.-Q.; Liu, J.-M.; Feng, S.-S.; Chen, J.-G.
Abstract: Using a GHZ-class state as a quantum channel, we investigate the remote preparation of a qubit state and that of an entangled state in noisy environments. By analytically solving the master equation in Lindblad form, we first obtain the time evolution of the GHZ-class quantum channel. Then the influence of the noises on the process of remote state preparation is considered through analytical derivation of the fidelity and numerical calculations of the corresponding average fidelity. Our results show that the fidelity depends on the noise type, the state to be remotely prepared, the GHZ-class state and the decoherence rate. Moreover, it is found that no matter whether the qubit state or the entangled state is to be remotely prepared, the maximally entangled quantum channel has a relatively stronger ability to resist the influence of noises. Besides, the effect of the bit-phase flip noise on the average fidelity is relatively stronger than that of the bit flip noise or phase flip noise. © 2011 IOP Publishing Ltd.
Tue, 14 Jun 2011 00:00:00 GMThttps://scholarbank.nus.edu.sg/handle/10635/978032011-06-14T00:00:00Z
- Remote preparation of a three-particle state via positive operator-valued measurementhttps://scholarbank.nus.edu.sg/handle/10635/97801Title: Remote preparation of a three-particle state via positive operator-valued measurement
Authors: Liu, J.-M.; Feng, X.-L.; Oh, C.H.
Abstract: We present a scheme to remotely prepare an arbitrary three-particle pure state in real Hilbert space by using three bipartite partially entangled pairs as a quantum channel, and then generalize it to the tripartite equatorial-like case. Our results show that remote preparation of the three-particle state both in real space and in imaginary space can be probabilistically achieved with unity fidelity by performing an appropriate three-particle projective measurement at the sender's side and an optimal positive operator-valued measurement at the receiver's side. Moreover, the probability of success of our scheme is determined by the smaller parameters of the three initial entangled pairs. © 2009 IOP Publishing Ltd.
Thu, 01 Jan 2009 00:00:00 GMThttps://scholarbank.nus.edu.sg/handle/10635/978012009-01-01T00:00:00Z