High-quality long-distance entanglement is essential for both quantum communication and scalable networks. Entanglement purification to distill high-quality from low-quality in a noisy environment it plays key role repeaters. The previous significant experiments require two pairs of entangled states were demonstrated table-top. Here we propose report high-efficiency using only one pair hyperentangled states. We also demonstrate its practical application entanglement-based distribution (QKD)....

Quantum teleportation provides a way to transmit unknown quantum states from one location another. In the world, multilevel systems which enable high-dimensional are more prevalent. Therefore, completely rebuild of single particle remotely, needs teleport (high-dimensional) states. Here, we demonstrate in three-dimensional six-photon system. We exploit spatial mode photon as system, use two auxiliary entangled photons realize deterministic Bell state measurement. The fidelity process matrix...

Experimental demonstration of beating the channel capacity limit for superdense coding with high-dimensional entanglement.

Communication in a network generally takes place through sequence of intermediate nodes connected by communication channels. In the standard theory communication, it is assumed that embedded classical spacetime, where relative order different well defined. principle, quantum spacetime could allow points between sender and receiver to be coherent superposition. Here we experimentally realize tabletop simulation this exotic possibility on photonic system, demonstrating high-fidelity...

Abstract Bell non-locality plays a fundamental role in quantum theory. Numerous tests of the inequality have been reported as ground-breaking discovery theorem. Up to now, however, most discussions scenario focused on single pair entangled particles distributed only two separated observers. Recently, it has shown surprisingly that multiple observers can share from an using method weak measurement without post-selection [Phys. Rev. Lett. 114 , 250401 (2015)]. Here we report observation double...

High-dimensional entanglement promises to greatly enhance the performance of quantum communication and enable advantages unreachable by qubit entanglement. One great challenges, however, is reliable production, distribution, local certification high-dimensional sources In this Letter, we present an optical setup capable producing states with exceptionally high level scalability, control, quality that, together novel techniques, achieve highest amount recorded so far. We showcase in...

In the context of continuous progress big data and artificial intelligence technology, hybrid genetic algorithm has been proved to be an effective means deal with complex optimization problems high-rise building structures. Based on algorithm, this paper comprehensively analyzes discusses wind resistance design tall buildings, summarizes current research status emphasizes attention load characteristics, puts forward a method considering joint probability distribution speed direction,...

Abstract Shared entanglement can significantly amplify classical correlations between systems interacting over a limited quantum channel. A natural avenue is to use of the same dimension as channel because this allows for unitary encodings, which preserve global coherence until measurement performed. Contrasting this, distributed task based on qubit demonstrated, irreversible encoding operations outperform any possible coherence‐preserving protocol. This corresponds using high‐dimensional...

High-dimensional entanglement enriches our understanding of and shows many advantages in quantum communications tasks, so its long-distance distribution is a key technology. Here, we use multicore fiber to distribute four-dimensional (4D) over 11 km. The observed fidelity <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mi>F</mml:mi> <mml:mo>=</mml:mo> <mml:mn>0.921</mml:mn> <mml:mo>±</mml:mo> <mml:mn>0.001</mml:mn> </mml:math> , which feasible for...

We use hyper-entanglement to experimentally realize deterministic entanglement swapping based on quantum Elegant Joint Measurements. These are joint projections of two qubits onto highly symmetric, iso-entangled, bases. report measurement fidelities no smaller than $97.4\%$. showcase the applications these measurements by using procedure demonstrate correlations in form proof-of-principle violations both bilocal Bell inequalities and more stringent correlation criteria corresponding full...

Quantum theory allows information to flow through a single device in coherent superposition of two opposite directions, resulting into situations where the input-output direction is indefinite. Here we introduce theoretical method witness indefiniteness quantum device, and experimentally demonstrate it by constructing photonic setup that exhibits with statistical significance exceeding 69 standard deviations. Our results provide way characterize as resource for technologies enable tabletop...

The physical impact and the testability of Kochen-Specker (KS) theorem is debated because fact that perfect compatibility in a single quantum system cannot be achieved practical experiments with finite precision. Here, we follow proposal A. Cabello M. T. Cunha [Phys. Rev. Lett. 106, 190401 (2011)], present compatibility-loophole-free experimental violation an inequality noncontextual theories by two spatially separated entangled qutrits. A maximally qutrit-qutrit state fidelity as high...

How to properly certify the quantum function of a process (device) is one key problems in information science, particularly, for beyond its classical counterpart. To verify teleportation critical task because fundamental roles communication and computation. Here, we experimentally certified nonclassical with setting by random robustness introduced [Phys. Rev. Lett. 119, 110501 (2017)]. Our results show that convenient powerful verifying entanglement.

In a measurement-device-independent or quantum-refereed protocol, referee can verify whether two parties share entanglement Einstein-Podolsky-Rosen (EPR) steering without the need to trust either of their devices. The for trusting party is substituted by quantum channel between and that party, through which encodes measurements be performed on party's subsystem in set nonorthogonal states. this Letter, an EPR-steering inequality adapted as witness, trust-free experimental verification higher...

Entanglement-based quantum communication offers an increased level of security in practical secret shared key distribution. One the fundamental principles enabling this security---the fact that interfering with one photon will destroy entanglement and thus be detectable---is also greatest obstacle. Random encounters traveling photons, losses, technical imperfections make noise inevitable part any scheme, severely limiting distance, rate, environmental conditions which distribution can...

The physics associated with multipartite high-dimensional entanglement is different from that of two-dimensional entanglement. Therefore, preparing entanglements linear optics challenging. This study proposes a preparation protocol multiphoton GHZ state arbitrary dimensions for optical systems. Auxiliary realize gate to connect the entangled pairs state. Specifically, we use path degrees freedom photons prepare four-partite, three-dimensional Our method can be extended other generate in any...

We experimentally show that nonlocality can be produced from single-particle contextuality by using two-particle correlations which do not violate any Bell inequality themselves. This demonstrates come an a priori different simpler phenomenon, and connects nonlocality, the two critical resources for, respectively, quantum computation secure communication. From perspective of information, our experiment constitutes proof principle systems used simultaneously for both

Many quantum information tasks rely on entanglement, which is used as a resource, for example, to enable efficient and secure communication. Typically, noise, accompanied by loss of reduces the efficiency protocols. We develop demonstrate experimentally superdense coding scheme with where decrease entanglement in Alice's encoding state does not reduce transmission. Having almost fully dephased classical two-photon polarization at time concurrence $0.163\pm0.007$, we reach values mutual close...

Bell-state measurements (BSMs) play a vital role in quantum information. However, there is no definite solution of how to realize high-dimensional (HDBSMs). In this paper, we present scheme for realizing arbitrary two-particle BSMs by auxiliary entanglement. our scheme, the maximally entangled states with different degrees freedom are used as states, and then HDBSM can be achieved implementing Bell measurement freedom. We detailed three- four-dimensional general formula states. Furthermore,...

Abstract Quantum entanglement is one of the most important resources in quantum information. In recent years, research mainly focused on increase number entangled qubits or high-dimensional two particles. Compared with qubit states, multipartite states have beneficial properties and are powerful for constructing networks. However, there few studies due to difficulty creating such states. this paper, we experimentally prepared a state $$\left|{\Psi }_{442}\right\rangle...

Non-Hermitian quantum metrology, an emerging field at the intersection of estimation and non-Hermitian physics, holds promise for revolutionizing precision measurement. Here, we present a comprehensive investigation parameter in regime, with special focus on achieving Heisenberg scaling. We introduce concise expression Fisher information (QFI) that applies to general Hamiltonians, enabling analysis these systems. Our findings unveil remarkable potential systems attain scaling 1/ t , where...

Sequential weak measurements of non-commuting observables is not only fundamentally interesting in quantum measurement but also shown potential various applications. The previous reported methods, however, can realize limited sequential experimentally. In this Letter, we propose the realization arbitrary and experimentally demonstrate for first time values three Pauli by using genuine single photons. results presented here will improve our understanding measurement, e.g. testing...