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Quantum entanglement and decoherence are the two counterforces of many quantum technologies and protocols. For example, while quantum teleportation is fueled by a pair of maximally entangled resource qubits, it is vulnerable to decoherence. Here, we propose an efficient quantum teleportation protocol in the presence of pure decoherence and without entangled resource qubits entering the Bell-state measurement. Instead, we use multipartite hybrid entanglement between the auxiliary qubits and their local environments within the open-quantum system context. With a hybrid-entangled initial state, it is the decoherence that allows us to achieve high fidelities. We demonstrate our protocol in an all-optical experiment. [ABSTRACT FROM AUTHOR]

The article presents a research study where researchers construct an non-Hermiticity (NH) system in a new configuration along the synthetic orbital angular momentum (OAM) dimension in a degenerate cavity. researchers have developed a unique method to explore the band structure along the synthetic OAM dimension. It is evident that EPs along the OAM lattice have unique optical applications.

Quantum coherence, an essential feature of quantum mechanics allowing quantum superposition of states, is a resource for quantum information processing. Coherence emerges in a fundamentally different way for nonidentical and identical particles. For the latter, a unique contribution exists linked to indistinguishability that cannot occur for nonidentical particles. Here we experimentally demonstrate this additional contribution to quantum coherence with an optical setup, showing that its amount directly depends on the degree of indistinguishability and exploiting it in a quantum phase discrimination protocol. Furthermore, the designed setup allows for simulating fermionic particles with photons, thus assessing the role of exchange statistics in coherence generation and utilization. Our experiment proves that independent indistinguishable particles can offer a controllable resource of coherence and entanglement for quantum-enhanced metrology. [ABSTRACT FROM AUTHOR]

We present spectral hole-burning measurements of the 4I9/2→4F3/2 transition in Nd3+:YLiF4. The isotope shifts of Nd3+ can be directly resolved in the optical absorption spectrum. We report atomic frequency comb storage with an echo efficiency of up to 35% and a memory bandwidth of 60 MHz in this material. The interesting properties show the potential of this material for use in both quantum and classical information processing [ABSTRACT FROM AUTHOR]

The article presents research report on zero–trade-off multiparameter quantum estimation via simultaneously saturating multiple Heisenberg uncertainty relations. Topics include highest precisions for multiple parameters at the same time requires the saturation of multiple Heisenberg uncertainty relations; and ultimate precisions for multiple parameters, our work marks an important step in multiparameter quantum metrology with wide implications.

The article presents a study on the reduction of quantum measurement back action in work distributions through collective calculation. It outlines the estimation of work fluctuation based on estimations on the coherence in energy in quantum thermodynamics. An overview of its experimental application in optical systems is also provided.

The article offers information on a study regarding beating the channel capacity limit for superdense coding (SDC) with entangled ququarts. It mentions that the SDC with high-dimensional entanglement is promising in the future. It states that the photon pairs are generated from ppKTP, the overall detection efficiency can be as high when using careful alignment and superconductor detectors.

Full quantum state tomography (FQST) plays a unique role in the estimation of the state of a quantum system without a priori knowledge or assumptions. Unfortunately, since FQST requires informationally (over)complete measurements, both the number of measurement bases and the computational complexity of data processing suffer an exponential growth with the size of the quantum system. A 14-qubit entangled state has already been experimentally prepared in an ion trap, and the data processing capability for FQST of a 14-qubit state seems to be far away from practical applications. In this paper, the computational capability of FQST is pushed forward to reconstruct a 14-qubit state with a run time of only 3.35 hours using the linear regression estimation (LRE) algorithm, even when informationally overcomplete Pauli measurements are employed. The computational complexity of the LRE algorithm is first reduced from ∼1019 to ∼1015 for a 14-qubit state, by dropping all the zero elements, and its computational efficiency is further sped up by fully exploiting the parallelism of the LRE algorithm with parallel Graphic Processing Unit (GPU) programming. Our result demonstrates the effectiveness of using parallel computation to speed up the postprocessing for FQST, and can play an important role in quantum information technologies with large quantum systems. [ABSTRACT FROM AUTHOR]