共查询到20条相似文献,搜索用时 31 毫秒
1.
《Physics letters. A》2005,339(6):430-439
We propose a scheme by which two parties can secretly and simultaneously exchange messages. The scheme requires the two parties to share entanglement and both to perform Bell-state measurements. Only two out of the four Bell states are required to be distinguished in the Bell-state measurements, and thus the scheme is experimentally feasible using only linear optical means. Generalizations of the scheme to high-dimensional systems and to multipartite entanglement are considered. We show also that the proposed scheme works even if the two parties do not possess shared reference frames. 相似文献
2.
Multiparty Quantum Secret Sharing of Classical Message using Cavity Quantum Electrodynamic System 下载免费PDF全文
An experimental feasible scheme of multiparty secret sharing of classical messages is proposed, based on a cavity quantum electrodynamic system. The secret messages are imposed on atomic Bell states initially in the sender's possession by local unitary operations. By swapping quantum entanglement of atomic Bell states, the secret messages are split into several parts and each part is distributed to a separate party. In this case, any subset of the entire party group can not read out the secret message but the entirety via mutual cooperations. In this scheme, to discriminate atomic Bell states, additional classical fields are employed besides the same highlydetuned single-mode cavities used to prepare atomic Bell states. This scheme is insensitive to the cavity decay and the thermal field, and usual joint Bell-state measurements are unnecessary. 相似文献
3.
We present an experimentally feasible one-step discrimination scheme on Bell bases with trapped ions, and then generalize it to the case of N-ion Greenberger-Horne-Zeilinger (GHZ) bases. In the scheme, all the orthogonal and complete N-ion GHZ internal states can be exactly discriminated only by one step, and thus it takes very short time. Moreover, the scheme is insensitive to thermal motion and dose not require the individual addressing of the ions. The Bell-state and GHZ-state one-step discrimination scheme can be widely used in quantum information processing based on ion-trap set-up. 相似文献
4.
A scheme, in which cross-Kerr nonlinearity is used for the Bell-state measurements and preparation of the resource of entanglement, is proposed for teleporting an entangled 2-photon state by using two polarization-photon Bell states as quantum channel based on cross-Kerr nonlinearity combined with linear optics elements such as polarization beam splitters and half wave plates. Teleportation of the entangled 2-photon polarization state can realized with certainty in principle. 相似文献
5.
A protocol for complete and nondestructive atomic Bell‐state analysis by using inverse engineering is presented. The setups for the Bell‐state analysis contain four atoms trapped in four separated cavities, respectively. The laser pulses designed by inverse engineering help in the manipulation of the transitions of atoms in a robust manner. By using the protocol, the information for distinguishing four Bell states of two information‐carrying atoms is encoded on two auxiliary atoms. Therefore, the four Bell states can be distinguished without being destroyed by detecting the states of the two auxiliary atoms. Moreover, as shown by the numerical simulations, the protocol has high successful probabilities to distinguish four Bell states when decoherence is considered. Thus, the protocol may provide some helpful perspectives for the quantum information tasks based on Bell states. 相似文献
6.
A new application of cluster states is investigated for quantum information splitting (QIS) of an arbitrary three-qubit state. In our scheme, a four-qubit cluster state and a Bell state are shared by a sender (Alice), a controller (Charlie), and areceiver (Bob). Both the sender and controller only need to perform Bell-state measurements (BSMs), the receiver can reconstruct the arbitrary three-qubit state by performing some appropriately unitary transformations on his qubits after he knows the measured results of both the sender and the controller. This QIS scheme is deterministic. 相似文献
7.
Deterministic nondestructive state analysis for polarization-spatial-time-bin hyperentanglement with cross-Kerr nonlinearity 下载免费PDF全文
We present a deterministic nondestructive hyperentangled Bell state analysis protocol for photons entangled in three degrees of freedom(DOFs),including polarization,spatial-mode,and time-bin DOFs.The polarization Bell state analyzer and spatial-mode Bell state analyzer are constructed by polarization parity-check quantum nondemolition detector(P-QND)and spatial-mode parity-check quantum nondemolition detector(S-QND)using cross-Kerr nonlinearity,respectively.The time-bin Bell state analyzer is constructed by the swap gate for polarization state and time-bin state of a photon(P-T swap gate)and P-QND.The Bell states analyzer for one DOF will not destruct the Bell states of other two DOFs,so the polarization-spatial-time-bin hyperentangled Bell states can be determinately distinguished without destruction.This deterministic nondestructive state analysis method has useful applications in quantum information protocols. 相似文献
8.
van Houwelingen JA Brunner N Beveratos A Zbinden H Gisin N 《Physical review letters》2006,96(13):130502
We present a novel Bell-state analyzer (BSA) for time-bin qubits allowing the detection of three out of four Bell states with linear optics, two detectors, and no auxiliary photons. The theoretical success rate of this scheme is 50%. Our new BSA demonstrates the power of generalized quantum measurements, known as positive operator valued measurements. A teleportation experiment was performed to demonstrate its functionality. We also present a teleportation experiment with a fidelity larger than the cloning limit. 相似文献
9.
Faithful long-distance quantum teleportation necessitates prior
entanglement distribution between two communicated locations. The
particle carrying on the unknown quantum information is then
combined with one particle of the entangled states for Bell-state
measurements, which leads to a transfer of the original quantum
information onto the other particle of the entangled states. However
in most of the implemented teleportation experiments nowadays, the
Bell-state measurements are performed even before successful
distribution of entanglement. This leads to an instant collapse of
the quantum state for the transmitted particle, which is actually a
single-particle transmission thereafter. Thus the true distance for
quantum teleportation is, in fact, only in a level of meters. In the
present experiment we design a novel scheme which has overcome this
limit by utilizing fiber as quantum memory. A complete quantum
teleportation is achieved upon successful entanglement distribution
over 967 meters in public free space. Active feed-forward control
techniques are developed for real-time transfer of quantum
information. The overall experimental fidelities for teleported
states are better than 89.6%, which signify high-quality
teleportation. 相似文献
10.
11.
基于弱非线性及线性光学元件提出非破坏性测量两光子Bell态及三光子 Greenberger-Horne-Zeilinger (GHZ)态方案. 方案中, 首先应用光束分束器及交叉克尔非线性介质对两光子Bell态进行对称性分析, 进而结合控制非门提出三光子分析方案实现对八个三光子GHZ态完全且非破坏性区分.
关键词:
Bell态测量
Greenberger-Horne-Zeilinger态测量
弱非线性
量子非破坏性测量 相似文献
12.
13.
We present a scheme for quantum superdense coding with hyperentanglement,in which the sender can transfer four bits of classical information by sending only one photon.The important device in the scheme is the hyperentangled Bell-state analyzer in both polarization and frequency degrees of freedom,which is also constructed in the paper by using a quantum nondemolition detector assisted by cross-Kerr nonlinearity.Our scheme can transfer more information with less resources than the existing schemes and is nearly deterministic and nondestructive. 相似文献
14.
We present a parametric source which allows the engineering of polarization-momentum hyperentangled two photon states based
on linear optics and a single type-I nonlinear crystal. The nonlocal character of these states has been verified by various
tests, including the “All Versus Nothing” test of local realism [A. Cabello, Phys. Rev. Lett. 87, 010403 (2001)], which represents a generalization of the GHZ to the case of two entangled particles and two observers. We
have also created a complete and deterministic Bell-state measurement by a novel experimental scheme which adopts polarization-momentum
hyper-entanglement and requires linear optics and single photon detectors.
The text was submitted by the authors in English. 相似文献
15.
G. P. Miroshnichenko 《Journal of Experimental and Theoretical Physics》2011,112(6):923-931
A theory of a discrete photodetection method is developed in which an atomic packet in a microresonator is used as a probe.
Such a detector is adjusted by selecting the number of atoms in the packet, the constant of interaction between the mode under
study and atoms and the interaction duration. The possibility is analyzed for using this detector to distinguish one-photon
and two-photon Fock states and applications in protocols of linear optical quantum measurements and communications. A protocol
of a Bell-state analyzer is prepared that allows one to distinguish all the four Bell states constructed on the polarization
states of a photon pair. 相似文献
16.
We present a device-independent protocol to test if a given black-box measurement device is entangled, that is, has entangled eigenstates. Our scheme involves three parties and is inspired by entanglement swapping; the test uses the Clauser-Horne-Shimony-Holt Bell inequality, checked between each pair of parties. In the case where all particles are qubits, we characterize quantitatively the deviation of the measurement device from a perfect Bell-state measurement. 相似文献
17.
In a photonic realization of qubits the implementation of quantum logic is rather difficult due to the extremely weak interaction
on the few photon level. On the other hand, in these systems interference is available to process the quantum states. We formalize
the use of interference by the definition of a simple class of operations which include linear-optical elements, auxiliary
states and conditional operations.
We investigate an important subclass of these tools, namely linear-optical elements and auxiliary modes in the vacuum state.
For these tools, we are able to extend a previous qualitative result, a no-go theorem for perfect Bell-state analyzer on two
qubits in polarization entanglement, by a quantitative statement. We show that within this subclass it is not possible to
discriminate unambiguously four equiprobable Bell states with a probability higher than 50%.
Received: 18 July 2000 / Revised version: 15 September 2000 / Published online: 6 December 2000 相似文献
18.
We propose a scheme for optical realization of deterministic entanglement concentration of polarized photons. To overcome the difficulty due to the lack of sufficiently strong interactions between photons, teleportation is employed to transfer the polarization states of two photons onto the path and polarization states of a third photon, which is made possible by the recent experimental realization of the deterministic and complete Bell state measurement. Then the required positive operator-valued measurement and further operations can be implemented deterministically by using a linear optical setup. All these are within the reach of current technology. 相似文献
19.
Based on entanglement swapping, a quantum key distribution (QKD) scheme is proposed. In this scheme, the secret keys are formed by comparing initial Bell states and outcomes of entanglement swapping. Moreover, all initial Bell states prepared by Alice and Bob are completely arbitrary. As the classical information exchanged between two parties is very little, this QKD scheme has a high efficiency. In addition, in order to prevent eavesdropping, decoy particles are used. 相似文献
20.
We propose a scheme capable of performing complete Bell-state analysis for single-photon hybrid entangled state. Our single-photon state is encoded in both polarization and frequency degrees of freedom. The setup of scheme is composed of polarizing beam splitters, half wave plates, frequency shifters, and independent wavelength division multiplexers, which are feasible with current technology. We also show that, with this setup, we can perform the schemes for complete two-photon Bell-state analysis for polarization degree of freedom. Moreover, it can also be used to perform the teleportation scheme between different degrees of freedom. This setup may allow extensive applications in current quantum communications. 相似文献