Phys Rev Lett
August 2025
We present a least square state estimator regularized by state purity to accomplish the task of quantum state tomography and entanglement verification, and report an experimental validation on a superconducting processor. First, a scalable full-state tomography is achieved with state fidelity 0.8217(1) for the 9-qubit W state and 0.
View Article and Find Full Text PDFJ Chem Theory Comput
September 2025
The free energy profile (FE Profile) is essential for understanding chemical processes in complex systems. However, achieving sufficient sampling with an accurate potential in the FE profile calculations for chemical reactions in complex environments is often computationally prohibitive. The reference potential method (RPM) addresses this challenge by sampling configurations on a low-level potential energy surface (PES) and then computing the FE profile at a high-level one using thermodynamic perturbation correction, significantly reducing computational costs.
View Article and Find Full Text PDFSingle-photon imaging is an emerging technology in sensing that is capable of imaging and identifying remote objects under extreme conditions. However, it faces several challenges, such as low resolution and high noise, to do the task of object detection. In this work, we propose an enhanced You Only Look Once network to identify and localize objects within images generated by single-photon sensing.
View Article and Find Full Text PDFObjectives: To investigate factors that may influence humoral immunity post-vaccination with a COVID-19-inactivated vaccine (SC2IV).
Methods: A total of 1596 healthy individuals from the Seventh Affiliated Hospital, Sun Yat-sen University (1217) and Shenzhen Baotian Hospital (379) were enrolled in this study among which 694 and 218 participants were vaccinated with two-dose SC2IV, respectively. Physical examination indices were recorded.
The widely used organotin compounds are notorious for their acute toxicity. Experiments revealed that organotin might cause reproductive toxicity by reversibly inhibiting animal aromatase functioning. However, the inhibition mechanism is obscure, especially at the molecular level.
View Article and Find Full Text PDFPhys Rev Lett
October 2019
In a measurement-device-independent or quantum-refereed protocol, a referee can verify whether two parties share entanglement or Einstein-Podolsky-Rosen (EPR) steering without the need to trust either of the parties or their devices. The need for trusting a party is substituted by a quantum channel between the referee and that party, through which the referee encodes the measurements to be performed on that party's subsystem in a set of nonorthogonal quantum states. In this Letter, an EPR-steering inequality is adapted as a quantum-refereed EPR-steering witness, and the trust-free experimental verification of higher dimensional quantum steering is reported via preparing a class of entangled photonic qutrits.
View Article and Find Full Text PDFPhys Rev Lett
February 2019
The set of all qubit states that can be steered to by measurements on a correlated qubit is predicted to form an ellipsoid-called the quantum steering ellipsoid-in the Bloch ball. This ellipsoid provides a simple visual characterization of the initial two-qubit state, and various aspects of entanglement are reflected in its geometric properties. We experimentally verify these properties via measurements on many different polarization-entangled photonic qubit states.
View Article and Find Full Text PDFWe report the discovery of two new invariants for three-qubit states which, similarly to the three-tangle, are invariant under local unitary transformations and permutations of the parties. These quantities have a direct interpretation in terms of the anisotropy of pairwise spin correlations. Applications include a universal ordering of pairwise quantum correlation measures for pure three-qubit states; trade-off relations for anisotropy, three-tangle and Bell nonlocality; strong monogamy relations for Bell inequalities, Einstein-Podolsky-Rosen steering inequalities, geometric discord and fidelity of remote state preparation (including results for arbitrary three-party states); and a statistical and reference-frame-independent form of quantum secret sharing.
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