Implementation of a nonlocal multi-qubit conditional phase gate is an essential requirement in some quantum infor- mation processing （QIP） tasks. Recently, a novel solid-state cavity quantum electrodynamics （QED） ...Implementation of a nonlocal multi-qubit conditional phase gate is an essential requirement in some quantum infor- mation processing （QIP） tasks. Recently, a novel solid-state cavity quantum electrodynamics （QED） system, in which the nitrogen-vacancy （NV） center in diamond is coupled to a microtoroidal resonator （MTR）, has been proposed as a poten- tial system for hybrid quantum information and computing. By virtue of such systems, we present a scheme to realize a nonlocal N-qubit conditional phase gate directly. Our scheme employs a cavity input-output process and single-photon interference, without the use of any auxiliary entanglement pair or classical communication. Considering the currently available technologies, our scheme might be quite useful among different nodes in quantum networks for large-scaled QIP.展开更多
Gilad Gour and Nolan R Wallach [J. Math. Phys. 51 112201(2010)] have proposed the 4-tangle and the square of the I concurrence. They also gave the relationship between the 4-tangle and the square of the I concurrence....Gilad Gour and Nolan R Wallach [J. Math. Phys. 51 112201(2010)] have proposed the 4-tangle and the square of the I concurrence. They also gave the relationship between the 4-tangle and the square of the I concurrence. In this paper, we give the expression of the square of the I concurrence and the n-tangle for six-qubit and eight-qubit by some local unitary transformation invariant. We prove that in six-qubit and eight-qubit states there exist strict monogamy laws for quantum correlations. We elucidate the relations between the square of the I concurrence and the n-tangle for six-qubit and eight-qubits. Especially, using this conclusion, we can show that 4-uniform states do not exist for eight-qubit states.展开更多
We construct a piecewise function to investigate some monogamy inequalities in terms of theαth power of concurrence and negativity(α≥2),entanglement of formation(α≥√2),and Tsallis-q entanglement(α≥1).These ine...We construct a piecewise function to investigate some monogamy inequalities in terms of theαth power of concurrence and negativity(α≥2),entanglement of formation(α≥√2),and Tsallis-q entanglement(α≥1).These inequalities are tighter than the existing results with detailed examples.Particularly,it is worth highlighting some classes of quantum states which can saturate these monogamy inequalities forα=2,4 and 6 in terms of concurrence and negativity and forα=1,2 and 3 in terms of Tsallis-q entanglement.展开更多
We present an efficient and simple protocol to unambiguously distinguish 2Nmutual orthogonal N-qubit Greenberger–Horne–Zeilinger states in polarization degree of freedom assisted by the frequency one. This scheme is...We present an efficient and simple protocol to unambiguously distinguish 2Nmutual orthogonal N-qubit Greenberger–Horne–Zeilinger states in polarization degree of freedom assisted by the frequency one. This scheme is based on N single photon Bell state measurements, which can be implemented non-locally. The success probability is100% in principle and our scheme is feasible with current technology. All the advantages make our protocol meaningful and practical in quantum information processing.展开更多
This paper proposes scalable schemes to generate the Greenberger-Horne-Zeilinger （GHZ） state and the cluster state with atomic ensembles via the dipole blockade mechanism on an atom chip, where the qubit is not carr...This paper proposes scalable schemes to generate the Greenberger-Horne-Zeilinger （GHZ） state and the cluster state with atomic ensembles via the dipole blockade mechanism on an atom chip, where the qubit is not carried by a single atom but an atomic ensemble. In the protocols, multiqubit entangled states are determinately prepared. Needlessness for single-photon source further decreases the complexity of the experiment. Based on the present laboratory technique, the schemes may be realized. The achieved results reveal a prospect for large-scale quantum communication and quantum computation.展开更多
We present a theoretical scheme for perfect teleportation of an unknown multipartite two-level state by a single EPR （Einstein-Podolsky-Rosen） pair, and then generalize it to multilevel, i.e., an N-quNit state can b...We present a theoretical scheme for perfect teleportation of an unknown multipartite two-level state by a single EPR （Einstein-Podolsky-Rosen） pair, and then generalize it to multilevel, i.e., an N-quNit state can be teleported by a single quNit entangled pair, with additional local unitary operations. The feature of the scheme is that teleporting a multipartite state with a reduced amount of entanglement costs less classical bits.展开更多
In this paper we propose a tripartite scheme for splitting an arbitrary 2-qubit quantum information by using two asymmetric W states as the quantum channel. In the schemem if the two recipients collaborate together, t...In this paper we propose a tripartite scheme for splitting an arbitrary 2-qubit quantum information by using two asymmetric W states as the quantum channel. In the schemem if the two recipients collaborate together, they can deterministically recover the quantum information by performing first a 4-qubit collective unitary operation and then two single-qubit unitary operations. In addition, since the asymmetric W states are employed as the quantum channel, the scheme is robust against decoherence.展开更多
Based on the Wu's scheme[C.F.Wu,J.L.Chen,L.C.Kwekl,and C.H.Ohel,Phys.Rev.A 73(2006)012310],we prepare the general N-qubit W state.We find that the concurrence of two qubits in general N-qubit Wstate is only relate...Based on the Wu's scheme[C.F.Wu,J.L.Chen,L.C.Kwekl,and C.H.Ohel,Phys.Rev.A 73(2006)012310],we prepare the general N-qubit W state.We find that the concurrence of two qubits in general N-qubit Wstate is only related to their coefficients and we successfully apply the general N-qubit W state to quantum state transferand quantum state prepare like that in two-qubit system.展开更多
We briefly describe the importance of division algebras and Poincaré conjecture in both mathematical and physical scenarios. Mathematically, we argue that using the torsion concept one can combine the formalisms ...We briefly describe the importance of division algebras and Poincaré conjecture in both mathematical and physical scenarios. Mathematically, we argue that using the torsion concept one can combine the formalisms of division algebras and Poincaré conjecture. Physically, we show that both formalisms may be the underlying mathematical tools in special relativity and cosmology. Moreover, we explore the possibility that by using the concept of n-qubit system, such conjecture may allow generalization the Hopf maps.展开更多
A symmetric and(n,n)-threshold scheme for a sender to partition his/her arbitrary single-qubit information among n recipients is proposed by using a newly constructed asymmetric(n+1)-qubit W state.Both the scheme in s...A symmetric and(n,n)-threshold scheme for a sender to partition his/her arbitrary single-qubit information among n recipients is proposed by using a newly constructed asymmetric(n+1)-qubit W state.Both the scheme in some given scenarios and the new W state are also discussed given.展开更多
基金Project supported by the National Fundamental Research Program of China(Grant No.2010CB923202)the Fundamental Research Funds for the Central Universities,Chinathe National Natural Science Foundation of China(Grant Nos.61177085,61205117,and 61377097)
文摘Implementation of a nonlocal multi-qubit conditional phase gate is an essential requirement in some quantum infor- mation processing （QIP） tasks. Recently, a novel solid-state cavity quantum electrodynamics （QED） system, in which the nitrogen-vacancy （NV） center in diamond is coupled to a microtoroidal resonator （MTR）, has been proposed as a poten- tial system for hybrid quantum information and computing. By virtue of such systems, we present a scheme to realize a nonlocal N-qubit conditional phase gate directly. Our scheme employs a cavity input-output process and single-photon interference, without the use of any auxiliary entanglement pair or classical communication. Considering the currently available technologies, our scheme might be quite useful among different nodes in quantum networks for large-scaled QIP.
文摘Gilad Gour and Nolan R Wallach [J. Math. Phys. 51 112201(2010)] have proposed the 4-tangle and the square of the I concurrence. They also gave the relationship between the 4-tangle and the square of the I concurrence. In this paper, we give the expression of the square of the I concurrence and the n-tangle for six-qubit and eight-qubit by some local unitary transformation invariant. We prove that in six-qubit and eight-qubit states there exist strict monogamy laws for quantum correlations. We elucidate the relations between the square of the I concurrence and the n-tangle for six-qubit and eight-qubits. Especially, using this conclusion, we can show that 4-uniform states do not exist for eight-qubit states.
基金Supported by Yunnan Provincial Research Foundation for Basic Research(Grant No.202001AU070041)Natural Science Foundation of Kunming University of Science and Technology(Grant No.KKZ3202007036)Basic and Applied Basic Research Funding Program of Guangdong Province(Grant Nos.2019A1515111097 and 2023A1515012074).
文摘We construct a piecewise function to investigate some monogamy inequalities in terms of theαth power of concurrence and negativity(α≥2),entanglement of formation(α≥√2),and Tsallis-q entanglement(α≥1).These inequalities are tighter than the existing results with detailed examples.Particularly,it is worth highlighting some classes of quantum states which can saturate these monogamy inequalities forα=2,4 and 6 in terms of concurrence and negativity and forα=1,2 and 3 in terms of Tsallis-q entanglement.
基金Supported by the National Natural Science Foundation of China under Grant No.11004258Fundamental Research Funds for the Central Universities Project under Grant No.CQDXWL-2012-014
文摘We present an efficient and simple protocol to unambiguously distinguish 2Nmutual orthogonal N-qubit Greenberger–Horne–Zeilinger states in polarization degree of freedom assisted by the frequency one. This scheme is based on N single photon Bell state measurements, which can be implemented non-locally. The success probability is100% in principle and our scheme is feasible with current technology. All the advantages make our protocol meaningful and practical in quantum information processing.
基金supported by the National Natural Science Foundation of China (Grant Nos.60878059,10947147,60677044,and 10574022)the Natural Science Foundation of Fujian Province of China (Grant No.2007J0002)
文摘This paper proposes scalable schemes to generate the Greenberger-Horne-Zeilinger （GHZ） state and the cluster state with atomic ensembles via the dipole blockade mechanism on an atom chip, where the qubit is not carried by a single atom but an atomic ensemble. In the protocols, multiqubit entangled states are determinately prepared. Needlessness for single-photon source further decreases the complexity of the experiment. Based on the present laboratory technique, the schemes may be realized. The achieved results reveal a prospect for large-scale quantum communication and quantum computation.
基金The project supported by the Fund from Hunan University of Science and Engineering
文摘We present a theoretical scheme for perfect teleportation of an unknown multipartite two-level state by a single EPR （Einstein-Podolsky-Rosen） pair, and then generalize it to multilevel, i.e., an N-quNit state can be teleported by a single quNit entangled pair, with additional local unitary operations. The feature of the scheme is that teleporting a multipartite state with a reduced amount of entanglement costs less classical bits.
基金supported by Program for New Century Excellent Talents in Universities of China under Grant No.NCET-06-0554the National Natural Science Foundation of China under Grant Nos.60677001 and 10747146+3 种基金the Science-Technology Fund of Anhui Province for Outstanding Youth under Grant No.06042087the Key Fund of the Ministry of Education of China under Grant No.206063the Natural Science Foundation of Guangdong Province under Grant Nos.06300345 and 7007806the Talent Foundation of High Education of Anhui Province for Outstanding Youth under Grant No.2009SQRZ056
文摘In this paper we propose a tripartite scheme for splitting an arbitrary 2-qubit quantum information by using two asymmetric W states as the quantum channel. In the schemem if the two recipients collaborate together, they can deterministically recover the quantum information by performing first a 4-qubit collective unitary operation and then two single-qubit unitary operations. In addition, since the asymmetric W states are employed as the quantum channel, the scheme is robust against decoherence.
基金National Natural Science Foundation of China under Grant Nos.10575017 and 10547106
文摘Based on the Wu's scheme[C.F.Wu,J.L.Chen,L.C.Kwekl,and C.H.Ohel,Phys.Rev.A 73(2006)012310],we prepare the general N-qubit W state.We find that the concurrence of two qubits in general N-qubit Wstate is only related to their coefficients and we successfully apply the general N-qubit W state to quantum state transferand quantum state prepare like that in two-qubit system.
文摘We briefly describe the importance of division algebras and Poincaré conjecture in both mathematical and physical scenarios. Mathematically, we argue that using the torsion concept one can combine the formalisms of division algebras and Poincaré conjecture. Physically, we show that both formalisms may be the underlying mathematical tools in special relativity and cosmology. Moreover, we explore the possibility that by using the concept of n-qubit system, such conjecture may allow generalization the Hopf maps.
基金the National Science Foundation of China under Grant(No.10574001)the Program of the Education Department of Anhui Province (2004kj029)the Talent Foundation of Anhui University
基金Supported by the Program for New Century Excellent Talents at the University of China (Grant No. NCET-06-0554)the National Natural Science Foundation of China (Grant Nos.60677001,10747146,and 10874122)+4 种基金the Science-Technology Fund of Anhui Province for Outstanding Youth (Grant No.06042087)the Key Fund of the Ministry of Education of China (Grant No.206063)the General Fund of the Educational Committee of Anhui Province (Grant No.2006KJ260B)the Natural Science Foundation of Guangdong Province of China (Grant Nos.06300345 and 7007806)the Talent Foundation of High Education of Anhui Province for Outstanding Youth (Grant No.2009SQRZ018)
文摘A symmetric and(n,n)-threshold scheme for a sender to partition his/her arbitrary single-qubit information among n recipients is proposed by using a newly constructed asymmetric(n+1)-qubit W state.Both the scheme in some given scenarios and the new W state are also discussed given.
