Publications by authors named "Dongkai Zhang"

Photonic orbital angular momentum (OAM) offers a promising platform for high-dimensional quantum information processing. While geometric phase (GP) is the crucial tool in enabling intrinsically fault-tolerant quantum computation, the measurement of GP using linear optics remains relatively unexplored in the OAM state space. Here, we propose an experimental scheme to detect GP shifts resulting from the cyclic evolution of OAM qutrit states.

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Leggett inequality states that nonlocal hidden-variable models might still be incompatible with the predictions of quantum physics. However, its theoretical and experimental demonstration is only in the scenario of 2-dimensional maximally entangled systems. An open question remains as to whether the Leggett inequality can be violated by nonmaximally entangled states.

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A variety of Chinese textual operational text data has been recorded during the operation and maintenance of the high-speed railway catenary system. Such defect text records can facilitate defect detection and defect severity analysis if mined efficiently and accurately. Therefore, in this context, this paper focuses on a specific problem in defect text mining, which is to efficiently extract defect-relevant information from catenary defect text records and automatically identify catenary defect severity.

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While linear or angular position and momentum can be linked by a continuous or discrete Fourier transform, there are some subtle problems in the analogous Fourier relationship between radial position and radial momentum in history. Here we exploit radial position and newly introduced radial momentum variables to report a radial version of light's diffraction. The mask with single or multiple radial slits confines the light to a radial transmission function.

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As is well known, angular position and orbital angular momentum (OAM) of photons are a conjugate pair of variables that have been extensively explored for quantum information science and technology. In contrast, the radial degrees of freedom remain relatively unexplored. Here we exploit the radial variables, i.

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We report a new scheme of ghost imaging by using a spatially structured pump in the Fourier domain of spontaneous parametric down-conversion for quantum-correlation-based pattern recognition. We exploit the mathematical feature of Laguerre-Gaussian mode's Fourier transform to describe the pump-modulated formation of a ghost image. Of particular interest is the experimental demonstration of a quantum equivalence of a Vander Lugt filter, based on which the nonlocal spiral phase contrast for vortex mapping and quantum-correlation-based human face recognition are implemented successfully.

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The role of ethylene and hydrogen peroxide (H₂O₂) in the induction of the alternative respiratory pathway (AP) in calluses from wild-type (WT) Arabidopsis and ethylene-insensitive mutant etr1-3 under salt stress was investigated. The capacity and the contribution of the AP to the total respiration were significantly induced by 100 mM sodium chloride (NaCl) in WT calluses but only slightly induced in etr1-3 calluses. Ethylene emission was enhanced in WT calluses under salt stress.

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