Demonstration of Einstein-Podolsky-Rosen Steering with Enhanced Subchannel Discrimination

Einstein-Podolsky-Rosen (EPR) steering describes a quantum nonlocal phenomenon in which one party can nonlocally affect the other's state through local measurements. It reveals an additional concept of quantum nonlocality, which stands between quantum entanglement and Bell nonlocality. Recently, a quantum information task named as subchannel discrimination (SD) provides a necessary and sufficient characterization of EPR steering. The success probability of SD using steerable states is higher than using any unsteerable states, even when they are entangled. However, the detailed construction of such subchannels and the experimental realization of the corresponding task are still technologically challenging. In this work, we designed a feasible collection of subchannels for a quantum channel and experimentally demonstrated the corresponding SD task where the probabilities of correct discrimination are clearly enhanced by exploiting steerable states. Our results provide a concrete example to operationally demonstrate EPR steering and shine a new light on the potential application of EPR steering.Comment: 16 pages, 8 figures, appendix include

Quantum Algorithm for Solving Quadratic Nonlinear System of Equations

High-dimensional nonlinear system of equations that appears in all kinds of fields is difficult to be solved on a classical computer, we present an efficient quantum algorithm for solving $n$-dimensional quadratic nonlinear system of equations. Our algorithm embeds the equations into a finite-dimensional system of linear equations with homotopy perturbation method and a linearization technique, then we solve the linear equations with quantum linear system solver and obtain a state which is $\epsilon$-close to the normalized exact solution of the original nonlinear equations with success probability $\Omega(1)$. The complexity of our algorithm is $O(\rm{poly}(\rm{log}(n/\epsilon)))$, which provides an exponential improvement over the optimal classical algorithm in dimension $n$.Comment: 9 pages; Modify the format error of tex source fil

1-(3,4-Dihy­droxy­phen­yl)hexan-1-one

In the title compound, C12H16O3, a fully extened hexyl carbon chain is attached to a benzene ring; the mean planes formed by the atoms in the benzene ring and the hexa­none are inclined at an angle 8.5 (2)° with respect to each other. In the crystal, inter­molecular O—H⋯O hydrogen bonds join the mol­ecules into an infinite sheet