The Experts below are selected from a list of 795618 Experts worldwide ranked by ideXlab platform
Huitian Wang - One of the best experts on this subject based on the ideXlab platform.
-
polarization interferometric prism a versatile tool for generation of vector fields measurement of topological charges and implementation of a spin orbit controlled Not Gate
Applied Physics Letters, 2021Co-Authors: Zhicheng Ren, Zimo Cheng, Xilin Wang, Jianping Ding, Huitian WangAbstract:Optical vortex and vector field are two important types of structured optical fields. Due to their wide applications and unique features in many scientific realms, the generation, manipulation, and measurement of such fields have attracted significant interest and become very important topics. However, most ways to generate vector fields have a trade-off among flexibility, efficiency, stability, and simplicity. Meanwhile, an easy and direct way to measure the topological charges, especially for a high order optical vortex, is still a challenge. Here we design and manufacture a prism: a polarization interferometric prism (PIP) as a single-element interferometer, which can conveniently convert an optical vortex to vector fields with high efficiency and be utilized to precisely measure the topological charge (both absolute value and sign) of an arbitrary optical vortex, even with a high order. Experimentally, we generate a variety of vector fields with global fidelity ranging from 0.963 to 0.993 and measure the topological charge of an optical vortex by counting the number of petals uniformly distributed over a ring on the output intensity patterns. As a versatile tool to generate, manipulate, and detect the spin-orbital state of single photons, PIP can also work in the single-photon regime for quantum information processing. In the experiment, the PIP is utilized as a spin–orbit controlled-Not Gate on the generated 28 two-qubit states, achieving the state fidelities ranging from 0.966 to 0.995 and demonstrating the feasibility of the PIP for single photons.
-
polarization interferometric prism a versatile tool for generation of vector fields measurement of topological charges and implementation of a spin orbit controlled Not Gate
arXiv: Optics, 2020Co-Authors: Zhicheng Ren, Zimo Cheng, Xilin Wang, Jianping Ding, Huitian WangAbstract:Optical vortex and vector field are two important types of structured optical fields. Due to their wide applications and unique features in many scientific realms, the generation, manipulation and measurement of such fields have attracted significant interest and become very important topics. However, most ways to generate vector fields have a trade-off among flexibility, efficiency, stability, and simplicity. Meanwhile, an easy and direct way to measure the topological charges, especially for high order optical vortex, is still a challenge. Here we design and manufacture a prism: polarization interferometric prism (PIP) as a single-element interferometer, which can conveniently convert an optical vortex to vector fields with high efficiency and be utilized to precisely measure the topological charge (both absolute value and sign) of an arbitrary optical vortex, even with a high order. Experimentally we generate a variety of vector fields with global fidelity ranging from 0.963 to 0.993 and measure the topological charge of an optical vortex by counting the number of petals uniformly distributed over a ring on the output intensity patterns. As a versatile tool to generate, manipulate and detect the spin-orbital state of single photons, PIP can also work in single-photon regime for quantum information processing. In experiment, the PIP is utilized as a spin-orbit Controlled-Not Gate on the generated 28 two-qubit states, achieving the state fidelities ranging from 0.966 to 0.995 and demonstrating the feasibility of the PIP for single photons.
F De Martini - One of the best experts on this subject based on the ideXlab platform.
-
contextual optimal and universal realization of the quantum cloning machine and of the Not Gate
Physical Review Letters, 2004Co-Authors: F De Martini, Daniele Pelliccia, Fabio SciarrinoAbstract:A simultaneous realization of the universal optimal quantum cloning machine and of the universal-Not Gate by a quantum injected optical parametric amplification, is reported. The two processes, forbidden in their exact form for fundamental quantum limitations, are found universal and optimal, and the measured fidelity F<1 is found close to the limit values evaluated by quantum theory. This work may enlighten the yet little explored interconnections of fundamental axiomatic properties within the deep structure of quantum mechanics.
-
teleportation scheme implementing the universal optimal quantum cloning machine and the universal Not Gate
Physical Review Letters, 2004Co-Authors: Marco Ricci, C Sias, Fabio Sciarrino, F De MartiniAbstract:By a significant modification of the standard protocol of quantum state teleportation, two processes "forbidden" by quantum mechanics in their exact form, the universal Not Gate and the universal optimal quantum cloning machine, have been implemented contextually and optimally by a fully linear method. In particular, the first experimental demonstration of the tele-UNot Gate, a novel quantum information protocol, has been reported. The experimental results are found in full agreement with theory.
-
contextual realization of the universal quantum cloning machine and of the universal Not Gate by quantum injected optical parametric amplification
Physical Review A, 2003Co-Authors: Daniele Pelliccia, C Sias, Fabio Sciarrino, Valentina Schettini, F De MartiniAbstract:A simultaneous, contextual experimental demonstration of the two processes of cloning an input qubit vertical bar {psi}> and of flipping it into the orthogonal qubit vertical bar {psi}{sup perpendicular>} is reported. The adopted experimental apparatus, a quantum-injected optical parametric amplifier is transformed simultaneously into a universal optimal quantum cloning machine and into a universal-Not quantum-information Gate. The two processes, indeed forbidden in their exact form for fundamental quantum limitations, were found to be universal and optimal, i.e., the measured fidelity of both processes F<1 was found close to the limit values evaluated by quantum theory. A contextual theoretical and experimental investigation of these processes, which may represent the basic difference between the classical and the quantum worlds, can reveal in a unifying manner the detailed structure of quantum information. It may also enlighten the yet little explored interconnections of fundamental axiomatic properties within the deep structure of quantum mechanics.
-
teleportation scheme implementing the universal optimal quantum cloning machine and the universal Not Gate
arXiv: Quantum Physics, 2003Co-Authors: Marco Ricci, C Sias, Fabio Sciarrino, F De MartiniAbstract:The universal quantum cloning machine and the universal Not Gate acting on a single qubit can be implemented very generally by slightly modifying the protocol of quantum state teleportation. The experimental demonstration of the 1 to 2 cloning process according to the above scheme has been realized for a qubit encoded in photon polarization.
-
experimental realization of the quantum universal Not Gate
Nature, 2002Co-Authors: F De Martini, Vladimír Bužek, Fabio Sciarrino, C SiasAbstract:In classical computation, a ‘bit’ of information can be flipped (that is, changed in value from zero to one and vice versa) using a logical Not Gate; but the quantum analogue of this process is much more complicated. A quantum bit (qubit) can exist simultaneously in a superposition of two logical states with complex amplitudes, and it is impossible1,2,3 to find a universal transformation that would flip the original superposed state into a perpendicular state for all values of the amplitudes. But although perfect flipping of a qubit prepared in an arbitrary state (a universal Not operation) is prohibited by the rules of quantum mechanics, there exists an optimal approximation2 to this procedure. Here we report the experimental realization of a universal quantum machine4 that performs the best possible approximation to the universal Not transformation. The system adopted was an optical parametric amplifier of entangled photon states, which also enabled us to investiGate universal quantum cloning.
Russell P. Cowburn - One of the best experts on this subject based on the ideXlab platform.
-
A magnetic shift register with out-of-plane magnetized layers
Nanotechnology, 2017Co-Authors: Rhodri Mansell, A. Beguivin, Dorothée Petit, A. Fernández-pacheco, Russell P. CowburnAbstract:Using out-of-plane magnetized layers, a lateral shift register made from discrete elements is demonstrated. By carefully designing the in-plane shape of the elements which make up the shift register, both the position of nucleation of new domains and the coercivity of the element can be controlled. The dipole field from a neighboring element, placed tens of nanometers away, creates a bias field on the nucleation site, which can be used to create a Not Gate. By chaining these Not Gates together, a shift register can be created where data bits consisting of neighboring layers with aligned magnetization are propaGated synchronously under a symmetric applied magnetic field. The operation of a 16 element shift register is shown, including field coupled data injection.
-
asymmetric magnetic Not Gate and shift registers for high density data storage
Applied Physics Letters, 2010Co-Authors: H T Zeng, Daniel Read, L Obrien, J Sampaio, E R Lewis, D Petit, Russell P. CowburnAbstract:We have developed an asymmetric ferromagnetic Not Gate and shift register optimized on a square grid. This gives rise to a two-dimensional storage scheme built up by tessellating an elementary data unit, which is scalable down to very narrow wire widths. The areal footprint of each storage unit is 15F2, where F is the minimum feature size. We experimentally demonstrate Not operations across a chain of three Gates made from Permalloy with F=60 nm, and present a functional 15-Gate, multichannel shift register with electrical injection, and optical readout.
-
spatially resolved observation of domain wall propagation in a submicron ferromagnetic Not Gate
Applied Physics Letters, 2005Co-Authors: Xiaobin Zhu, D A Allwood, Russell P. Cowburn, Gang Xiong, Peter GrutterAbstract:Domain-wall propagation under an external magnetic field in a submicron ferromagnetic ring integrated with a Not-junction is investiGated by magnetic force microscopy and micromagnetic modeling. Within a certain magnetic field range, one head-to-head or tail-to-tail domain wall propaGates in the structure. Magnetic fields above this range cause nucleation of additional domain walls in the ring structure while fields below this range are Not able to switch the Not-junction magnetization. This explicitly demonstrates the magnetization reversal, operation, and failure modes of a magnetic Not-junction.
-
submicrometer ferromagnetic Not Gate and shift register
Science, 2002Co-Authors: D A Allwood, M D Cooke, C C Faulkner, N Vernier, D Atkinson, Gang Xiong, Russell P. CowburnAbstract:An all-metallic submicrometer device is demonstrated experimentally at room temperature that performs logical Not operations on magnetic logic signals. When this two-terminal ferromagnetic structure is incorporated into a magnetic feedback loop, the junction performs a frequency division operation on an applied oscillating magnetic field. Up to 11 of these junctions are then directly linked together to create a magnetic shift register.
Jian-wei Pan - One of the best experts on this subject based on the ideXlab platform.
-
on demand semiconductor single photon source with near unity indistinguishability
International Photonics and Optoelectronics Meetings (2012) paper IF1A.3, 2012Co-Authors: Yujia Wei, Mete Atature, Christian Schneider, Sven Hofling, Martin Kamp, Jian-wei PanAbstract:We generate pulsed resonance fluorescence single photons on demand from a single, microcavity-embedded quantum dot with less than 0.3% background contributions and a Hong-Ou-Mandel interference visibility of 0.970(19). Two single photons are further used to implement a high-fidelity quantum controlled-Not Gate.
-
experimental realization of a controlled Not Gate with four photon six qubit cluster states
Physical Review Letters, 2010Co-Authors: Weibo Gao, Jian-wei Pan, Xingcan Yao, Otfried Guhne, Adan Cabello, Chengzhi Peng, Zengbing ChenAbstract:We experimentally demonstrate an optical controlled-Not (CNot) Gate with arbitrary single inputs based on a 4-photon 6-qubit cluster state entangled both in polarization and spatial modes. We first generate the 6-qubit state, and then, by performing single-qubit measurements, the CNot Gate is applied to arbitrary single input qubits. To characterize the performance of the Gate, we estimate its quantum process fidelity and prove its entangling capability. In addition, our results show that the Gate canNot be reproduced by local operations and classical communication. Our experiment shows that such hyper-entangled cluster states are promising candidates for efficient optical quantum computation.
-
Optical Nondestructive Controlled-Not Gate without Using Entangled Photons
Physical Review Letters, 2007Co-Authors: Xiao-hui Bao, Teng-yun Chen, Qiang Zhang, Jian Yang, Han Zhang, Tao Yang, Jian-wei PanAbstract: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 fidelity. The result shows a great improvement compared with previous experiments. Moreover, we also show that quantum parallelism is achieved in our Gate and the performance of the Gate can Not be reproduced by local operations and classical communications.
-
realization of a photonic controlled Not Gate sufficient for quantum computation
Physical Review Letters, 2004Co-Authors: Sara Gasparoni, Jian-wei Pan, Philip Walther, Terry Rudolph, Anton ZeilingerAbstract: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 only the use of linear optics, an entangled ancillary pair of photons, and postselection. The techniques developed in our experiment are of significant importance for quantum information processing with linear optics.
M Saffman - One of the best experts on this subject based on the ideXlab platform.
-
rydberg blockade controlled Not Gate and entanglement in a two dimensional array of neutral atom qubits
Physical Review A, 2015Co-Authors: Kara Maller, L Isenhower, Martin Lichtman, Tian Xia, Yuan Sun, M J Piotrowicz, Alex Carr, M SaffmanAbstract:We present experimental results on two-qubit Rydberg-blockade quantum Gates and entanglement in a two-dimensional qubit array. Without postselection against atom loss we achieve a Bell state fidelity of $0.73\ifmmode\pm\else\textpm\fi{}0.05$. The experiments are performed in an array of single Cs atom qubits with a site to site spacing of $3.8\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}\mathrm{m}$. Using the standard protocol for a Rydberg-blockade ${C}_{Z}$ Gate together with single qubit operations we create Bell states and measure their fidelity using parity oscillations. We analyze the role of ac Stark shifts that occur when using two-photon Rydberg excitation and show how to tune experimental conditions for optimal Gate fidelity.
-
deterministic entanglement of two neutral atoms via rydberg blockade
Physical Review A, 2010Co-Authors: Xianli Zhang, T G Walker, L Isenhower, A T Gill, M SaffmanAbstract:We demonstrate the deterministic entanglement of two individually addressed neutral atoms using a Rydberg blockade mediated controlled-Not Gate. Parity oscillation measurements reveal a Bell state fidelity of $F=0.58\ifmmode\pm\else\textpm\fi{}0.04$, which is above the entanglement threshold of $F=0.5$, without any correction for atom loss, and $F=0.71\ifmmode\pm\else\textpm\fi{}0.05$ after correcting for background collisional losses. The fidelity results are shown to be in good agreement with a detailed error model.
