IMPLEMENTATION OF SWAP GATE AND FREDKIN GATE USING LINEAR OPTICAL ELEMENTS

A scheme is proposed to directly implement the optical swap gate and quantum Fredkin gate based on the Mach–Zehnder interferometer (MZI). The distinct advantage of the present scheme is that ancilla single-photons are not needed. The optical swap gate is deterministic and does not need the photon number resolving detectors. The total success probability of the present Fredkin gate can reach 1/16 by using basic linear-optics elements.

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EFFICIENT SCHEME FOR PREPARING POLARIZATION-ENTANGLED PHOTONIC CLUSTER STATES BASED ON CROSS-KERR NONLINEARITY

International Journal of Quantum Information ◽

10.1142/s0219749911007915 ◽

2011 ◽

Vol 09 (05) ◽

pp. 1319-1327

Author(s):

MENG-ZHENG ZHU ◽

GUANG-YU YUAN

Keyword(s):

Cluster State ◽

Success Probability ◽

Kerr Nonlinearity ◽

Optical Systems ◽

Distinct Advantage ◽

Optical Elements ◽

Cluster States ◽

Present Scheme ◽

Linear Optical ◽

High Success Probability

A scheme is proposed for generating a polarization four-photon cluster, which is believed to be suitable to achieve the one-way quantum computing via single-qubit projective measurements, with the help of only cross-Kerr nonlinearity and current linear optical systems. Compared with the existing schemes, the distinct advantage of the present scheme is that cluster states can be achieved with high success probability close to unity. Our scheme is experimentally demanding but efficient. Based on the present scheme, the cluster state of 3N + 1 photons can be obtained with the help of linear optical elements.

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SCHEME FOR TELECLONING AN IONIC STATE WITHOUT JOINT MEASUREMENT VIA LINEAR OPTICS

International Journal of Quantum Information ◽

10.1142/s0219749908003748 ◽

2008 ◽

Vol 06 (04) ◽

pp. 929-934 ◽

Cited By ~ 1

Author(s):

FEI YAN ◽

MING YANG ◽

ZHUO-LIANG CAO

Keyword(s):

Quantum Channel ◽

W State ◽

Distinct Advantage ◽

Linear Optics ◽

Joint Measurement ◽

Optical Elements ◽

Ionic State ◽

Linear Optical ◽

Linear Optical Elements

We present a protocol for telecloning an ionic state to M distant users by using linear optical elements. The quantum channel used here is a (M + 1)-particle W state. The most distinct advantage of the current scheme is that it does not need a joint measurement required by the previous telecloning schemes.

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Analysis of circuit imperfections in BosonSampling

Quantum Information and Computation ◽

10.26421/qic15.5-6-8 ◽

2015 ◽

pp. 489-512

Author(s):

Anthony Leverrier ◽

Raul Garcia-Patron

Keyword(s):

Fault Tolerance ◽

Quantum Computer ◽

State Of The Art ◽

Optical Element ◽

Single Photons ◽

Linear Optics ◽

Tolerance Mechanism ◽

Optical Elements ◽

Full Quantum

BosonSampling is a problem where a quantum computer offers a provable speedup over classical computers. Its main feature is that it can be solved with current linear optics technology, without the need for a full quantum computer. In this work, we investigate whether an experimentally realistic BosonSampler can really solve BosonSampling without any fault-tolerance mechanism. More precisely, we study how the unavoidable errors linked to an imperfect calibration of the optical elements affect the final result of the computation. We show that the fidelity of each optical element must be at least 1 − O(1/n^2 ), where n refers to the number of single photons in the scheme. Such a requirement seems to be achievable with state-of-the-art equipment.

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Experimental Progress in Linear Optics Quantum Computing

Quantum Information and Computation ◽

10.26421/qic3.s-7 ◽

2003 ◽

Vol 3 (special) ◽

pp. 553-562

Author(s):

J.D. Franson ◽

M.M. Donegan ◽

M.J. Fitch ◽

B.C. Jacobs ◽

T.B. Pittman

Keyword(s):

Quantum Logic ◽

Logic Gates ◽

Memory Device ◽

High Fidelity ◽

Single Photons ◽

Linear Optics ◽

Optical Elements ◽

Quantum Logic Gates ◽

Feed Forward Control ◽

Logic Operations

Probabilistic quantum logic operations can be performed using linear optical elements and post-selection based on the results of measurements on ancilla photons. We review the results of a number of recent experiments in this area, including the demonstration of several quantum logic gates, the use of feed-forward control, a new source of single photons, and a quantum memory device for single photons. A high-fidelity approach in which the logic gates always produce an output will also be discussed.

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Entanglement of individual photon and atomic ensembles

Quantum Information and Computation ◽

10.26421/qic3.6-6 ◽

2003 ◽

Vol 3 (6) ◽

pp. 627-634

Author(s):

G.-P. Guo ◽

G.-C. Guo

Keyword(s):

Single Photon ◽

Collective Excitations ◽

Critical Element ◽

Linear Optics ◽

Atomic Ensembles ◽

Photon Detectors ◽

Present Scheme ◽

Single Photon Detectors ◽

Present Technique ◽

Individual Photon

Here we present an experimentally feasible scheme to entangle flying qubit (individual photon with polarization modes) and stationary qubit (atomic ensembles with long-lived collective excitations). This entanglement integrating two different species can act as a critical element for the coherent transfer of quantum information between flying and stationary qubits. The entanglement degree can be also adjusted expediently with linear optics. Furthermore, the present scheme can be modified to generate this entanglement in a way event-ready, with the employment of a pair of entangled photons. And then successful preparation can be unambiguously heralded by coincident between two single-photon detectors. Its application for individual photons quantum memory is also analyzed. The physical requirements of all those preparation and applications processing are moderate, and well fit the present technique.

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Efficient linear optics quantum computation

Quantum Information and Computation ◽

10.26421/qic1.s-4 ◽

2001 ◽

Vol 1 (Special) ◽

pp. 13-19

Author(s):

G.J. Milburn ◽

T. Ralph ◽

A. White ◽

E. Knill ◽

R. Laflamme

Keyword(s):

Quantum Computation ◽

Single Photon ◽

Quantum Algorithms ◽

Optical Nonlinearities ◽

Linear Optics ◽

Optical Elements ◽

Particle Detectors ◽

Feed Forward ◽

Single Electrons ◽

Photon Source

Two qubit gates for photons are generally thought to require exotic materials with huge optical nonlinearities. We show here that, if we accept two qubit gates that only work conditionally, single photon sources, passive linear optics and particle detectors are sufficient for implementing reliable quantum algorithms. The conditional nature of the gates requires feed-forward from the detectors to the optical elements. Without feed forward, non-deterministic quantum computation is possible. We discuss one proposed single photon source based on the surface acoustic wave guiding of single electrons.

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ontrolled implementation of two-photon controlled phase gate within a network

Quantum Information and Computation ◽

10.26421/qic10.9-10-7 ◽

2010 ◽

Vol 10 (9&10) ◽

pp. 821-828

Author(s):

Yan Xia ◽

Jie Song ◽

Zhen-Biao Yang ◽

Shi-Biao Zheng

Keyword(s):

Quantum Computer ◽

Photon Detectors ◽

Optical Elements ◽

Experimental Realization ◽

Two Photon ◽

Phase Gate ◽

Controlled Phase Gate ◽

Linear Optical ◽

Polarized Photons ◽

Linear Optical Elements

We propose a protocol to controlled implement the two-photon controlled phase gate within a network by using interference of polarized photons. The realization of this protocol is appealing due to the fact that the quantum state of light is robust against the decoherence, and photons are ideal carriers for transmitting quantum information over long distances. The proposed setup involves simple linear optical elements and the conventional photon detectors that only distinguish the vacuum and nonvacuum Fock number states. This can greatly simplify the experimental realization of a linear optical quantum computer.

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