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Related papers: Deterministic generation of a four-qubit W state u…

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Extending a previous result on the generation of two-photon generalized binomial field states, here we propose an efficient scheme to generate with high-fidelity, in a single-mode high-Q cavity, N-photon generalized binomial states with a…

Quantum Physics · Physics 2014-11-18 Rosario Lo Franco , Giuseppe Compagno , Antonino Messina , Anna Napoli

We introduce schemes for linear-optical quantum state generation. A quantum state generator is a device that prepares a desired quantum state using product inputs from photon sources, linear-optical networks, and postselection using photon…

Quantum Physics · Physics 2009-11-13 N. M. VanMeter , P. Lougovski , D. B. Uskov , K. Kieling , J. Eisert , Jonathan P. Dowling

The concept of directionally unbiased optical multiports is introduced, in which photons may reflect back out the input direction. A linear-optical implementation is described, and the simplest three-port version studied. Symmetry arguments…

Quantum Physics · Physics 2016-04-29 David S. Simon , Casey A. Fitzpatrick , Alexander V. Sergienko

Realizing a fully connected network of quantum processors requires the ability to distribute quantum entanglement. For distant processing nodes, this can be achieved by generating, routing, and capturing spatially entangled itinerant…

We report the characterization of a universal set of logic gates for one-way quantum computing using a four-photon `star' cluster state generated by fusing photons from two independent photonic crystal fibre sources. We obtain a fidelity…

Quantum Physics · Physics 2013-12-25 B. A. Bell , M. S. Tame , A. S. Clark , R. W. Nock , W. J. Wadsworth , J. G. Rarity

We devise an all-optical scheme for the generation of entangled multimode photonic states encoded in temporal modes of light. The scheme employs a nonlinear down-conversion process in an optical loop to generate one- and higher-dimensional…

Quantum Physics · Physics 2018-03-29 I. Dhand , M. Engelkemeier , L. Sansoni , S. Barkhofen , C. Silberhorn , M. B. Plenio

We analyze and compare three different schemes that can be used to generate entanglement between spin qubits in optically-active single solid-state quantum systems. Each scheme is based on first generating entanglement between the spin…

We present some deterministic schemes to construct universal quantum gates, that is, controlled- NOT, three-qubit Toffoli, and Fredkin gates, between flying photon qubits and stationary electron-spin qubits assisted by quantum dots inside…

Quantum Physics · Physics 2015-06-12 Hai-Rui Wei , Fu-Guo Deng

We report on the experimental generation of an entangled state with a spectrally pure heralded single-photon state and a weak coherent state. By choosing group-velocity matching in the nonlinear crystal, our system for producing entangled…

We show how one can deterministically generate photonic matrix product states with high bond and physical dimensions with an atomic array if one has access to a Rydberg-blockade mechanism. We develop both a quantum gate and an optimal…

Quantum Physics · Physics 2021-04-21 Zhi-Yuan Wei , Daniel Malz , Alejandro González-Tudela , J. Ignacio Cirac

We suggest and demonstrate a novel source of two-photon multipartite entangled states which exploits the transverse spatial structure of spontaneous parametric downconversion together with a programmable spatial light modulator (SLM). The…

Quantum Physics · Physics 2015-05-14 Simone Cialdi , Davide Brivio , Matteo G. A. Paris

We propose a scheme to implement a single-mode quantum filter, which selectively eliminates the one-photon state in a quantum state $\alpha|0>+\beta|1>+\gamma|2>$. The vacuum state and the two photon state are transmitted without any…

Quantum Physics · Physics 2009-11-07 XuBo Zou , K. Pahlke , W. Mathis

Entanglement is the quintessential quantum mechanical phenomenon understood to lie at the heart of future quantum technologies and the subject of fundamental scientific investigations. Mixture, resulting from noise, is often an unwanted…

Entanglement generation in polariton systems is fundamentally constrained by high losses and decoherence, which typically outweigh polariton nonlinearities. Here, we propose a conceptually different approach that uses optomechanical…

Integrated optics allow the generation and control of increasingly complex photonic states on chip based architectures. Here, we implement two entangled qutrits - a 9-dimensional quantum system - and demonstrate an exceptionally high degree…

Quantum Physics · Physics 2015-06-04 Christoph Schaeff , Robert Polster , Marcus Huber , Sven Ramelow , Anton Zeilinger

Time-bin qubits, where information is encoded in a single photon at different times, have been widely used in optical fiber and waveguide based quantum communications. With the recent developments in distributed quantum computation, it is…

We propose an all-optical setup, which couples different degrees of freedom of a single photon, to investigate entanglement generation by a common environment. The two qubits are represented by the photon polarization and Hermite-Gauss…

Deterministic photon-photon gates enable the controlled generation of entanglement between mobile carriers of quantum information. Such gates have thus far been exclusively realized in the optical domain and by relying on post-selection.…

Quantum physics allows for entanglement between microscopic and macroscopic objects, described by discrete and continuous variables, respectively. As in Schr\"odinger's famous cat gedanken experiment, a box enclosing the objects can keep…

Quantum Physics · Physics 2019-07-18 Bastian Hacker , Stephan Welte , Severin Daiss , Armin Shaukat , Stephan Ritter , Lin Li , Gerhard Rempe

Quantum states of light with many entangled photons are key resources for photonic quantum computing and quantum communication. In this work, we exploit a highly resource-efficient generation scheme based on a linear optical circuit…