English
Related papers

Related papers: An All Optical Fibre Quantum Controlled-NOT Gate

200 papers

We present and experimentally demonstrate a novel optical nondestructive controlled-NOT gate without using entangled ancilla. With much fewer measurements compared with quantum process tomography, we get a good estimation of the gate…

Quantum Physics · Physics 2009-11-13 Xiao-Hui Bao , Teng-Yun Chen , Qiang Zhang , Jian Yang , Han Zhang , Tao Yang , Jian-Wei Pan

A controlled-NOT logic gate based on conditional spectroscopy has been demonstrated recently for a pair of superconducting flux qubits [Plantenberg et al., Nature 447, 836 (2007)]. Here we study the fidelity of this type of gate applied to…

Quantum Physics · Physics 2011-08-23 Joydip Ghosh , Michael R. Geller

Optical qubits uniquely combine information transfer in optical fibers with a good processing capability and are therefore attractive tools for quantum technologies. A large challenge, however, is to overcome the low efficiency of two-qubit…

We present the first quantum controlled-NOT (CNOT) gate realized using a fiber-based indistinguishable photon-pair source in the 1.55 $\mu$m telecommunications band. Using this free-space CNOT gate, all four Bell states are produced and…

The initial proposal for scalable optical quantum computing required single photon sources, linear optical elements such as beamsplitters and phaseshifters, and photon detection. Here we demonstrate a two qubit gate using indistinguishable…

We report the first experimental demonstration of an optical quantum controlled-NOT gate without any path interference, where the two interacting path interferometers of the original proposals (Phys. Rev. A {\bf 66}, 024308 (2001), Phys.…

Quantum Physics · Physics 2009-11-11 Ryo Okamoto , Holger F. Hofmann , Shigeki Takeuchi , Keiji Sasaki

We report on the first experimental realization of optimal linear-optical controlled phase gates for arbitrary phases. The realized scheme is entirely flexible in that the phase shift can be tuned to any given value. All such controlled…

Quantum Physics · Physics 2015-05-19 Karel Lemr , Antonin Cernoch , Jan Soubusta , Konrad Kieling , Jens Eisert , Miloslav Dusek

We demonstrate complete characterization of a two-qubit entangling process - a linear optics controlled-NOT gate operating with coincident detection - by quantum process tomography. We use maximum-likelihood estimation to convert the…

Quantum Physics · Physics 2008-11-26 J. L. O'Brien , G. J. Pryde , A. Gilchrist , D. F. V. James , N. K. Langford , T. C. Ralph , A. G. White

We report a proof-of-principle demonstration of a probabilistic controlled-NOT gate for single photons. Single-photon control and target qubits were mixed with a single ancilla photon in a device constructed using only linear optical…

Quantum Physics · Physics 2009-11-10 T. B. Pittman , M. J. Fitch , B. C Jacobs , J. D. Franson

We report the first experimental demonstration of a quantum controlled-NOT gate for different photons, which is classically feed-forwardable. In the experiment, we achieved this goal with the use only of linear optics, an entangled…

Quantum Physics · Physics 2009-11-10 Sara Gasparoni , Jian-Wei Pan , Philip Walther , Terry Rudolph , Anton Zeilinger

Quantum networks provide a novel framework for quantum information processing, significantly enhancing system capacity through the interconnection of modular quantum nodes. Beyond the capability to distribute quantum states, the ability to…

Heralded entangling quantum gates are an essential element for the implementation of large-scale optical quantum computation. Yet, the experimental demonstration of genuine heralded entangling gates with free-flying output photons in linear…

Recent progress in integrated-optics technology has made photonics a promising platform for quantum networks and quantum computation protocols. Integrated optical circuits are characterized by small device footprints and unrivalled…

We propose a two-qubit optically controlled phase gate in quantum dot molecules via adiabatic passage and hole tunneling. Our proposal combines the merits of the current generation of vertically stacked self-assembled InAs quantum dots and…

Quantum Physics · Physics 2015-05-20 Li-Bo Chen , Wen Yang

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 show that it is possible to reduce the number of two-qubit gates needed for the construction of an arbitrary controlled-unitary transformation by up to two times using a tunable controlled-phase gate. On the platform of linear optics,…

Quantum Physics · Physics 2015-04-22 Karel Lemr , Karol Bartkiewicz , Antonín Černoch , Miloslav Dušek , Jan Soubusta

The promise of tremendous computational power, coupled with the development of robust error-correcting schemes, has fuelled extensive efforts to build a quantum computer. The requirements for realizing such a device are confounding:…

Quantum Physics · Physics 2011-08-17 J L O'Brien , G J Pryde , A G White , T C Ralph , D Branning

Hyperparallel quantum information processing outperforms its traditional parallel one in terms of channel capacity, low loss rate, and processing speed. We present a way for implementing a robust hyper-parallel optical controlled-phase-flip…

Quantum Physics · Physics 2020-08-05 Hai-Rui Wei , Yan-Bei Zheng , Ming Hua , Guo-Fu Xu

Quantum computers comprise elementary logic gates that initialize, control and measure delicate quantum states. One of the most important gates is the controlled-NOT, which is widely used to prepare two-qubit entangled states. The…

Quantum Physics · Physics 2024-01-04 Robert J. Chapman , Samuel Häusler , Giovanni Finco , Fabian Kaufmann , Rachel Grange

We experimentally demonstrate a programmable single-qubit quantum gate. This device applies a unitary phase shift operation to a data qubit with the value of the phase shift being fully determined by the state of a program qubit. Our linear…

Quantum Physics · Physics 2009-11-13 Michal Micuda , Miroslav Jezek , Miloslav Dusek , Jaromir Fiurasek
‹ Prev 1 2 3 10 Next ›