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- 摘要
- 关键词
- 实验方案
- 产品
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Linear and nonlinear optical effects in biophotonic structures using classical and nonclassical light
摘要： In this perspective article, we review the optical study of different biophotonic geometries and biological structures using classical and nonlinear regime, especially highlighting the link between these morphologies and modern biomedical research. Additionally, the importance of nonlinear optical study in biological research, beyond traditional cell imaging is also highlighted and described. Finally, we present a short introduction regarding nonclassical light and describe the new future perspective of quantum optical study in biology, revealing the link between quantum realm and biological research.
关键词： linear and nonlinear spectroscopy,nonclassical light,squeezed light,optics,ghost imaging,biophotonics,fluorescence spectroscopy
更新于2025-09-23 15:21:01
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Ghost imaging at an XUV free-electron laser
摘要： Here we present the results of a classical ghost imaging experiment accomplished at an XUV free-electron laser (FEL). To perform such experiment at an FEL source each x-ray pulse was transmitted through a moving diffuser, which created a noncorrelated speckled beam. This beam was then split in two identical branches by introducing a beam splitter in the form of a transmission grating. In one of these branches the sample was positioned. We demonstrate the possibility of image formation, a double bar in our case, in the beam that has never interacted with the sample. With this experiment we extend the quantum optics methodology to the FEL community.
关键词： XUV free-electron laser,speckle pattern,quantum optics,ghost imaging,transmission grating
更新于2025-09-23 15:19:57
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Ghost Spectroscopy with Classical Correlated Amplified Spontaneous Emission Photons Emitted by An Erbium-Doped Fiber Amplifier
摘要： We demonstrate wavelength-wavelength correlations of classical broad-band amplified spontaneous emission (ASE) photons emitted by an erbium-doped fiber amplifier (EDFA) in a wavelength regime around 1530 nm. We then apply these classical correlated photons in the framework of a real-world ghost spectroscopy experiment at a wavelength of 1533 nm to acetylene (C2H2) reproducing the characteristic absorption features of the C-H stretch and rotational bands. This proof-of-principle experiment confirms the generalization of an ASE source concept offering an attractive light source for classical ghost spectroscopy. It is expected that this will enable further disseminating ghost modality schemes by exploiting classical correlated photons towards applications in chemistry, physics and engineering.
关键词： spectral correlations,quantum optics,coherence,correlated photons,erbium-doped fiber amplifier,photon correlation modalities,ghost imaging,amplified spontaneous emission (ASE),spectroscopy,ghost spectroscopy,ghost modalities
更新于2025-09-19 17:15:36
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[IEEE 2018 28th International Telecommunication Networks and Applications Conference (ITNAC) - Sydney, Australia (2018.11.21-2018.11.23)] 2018 28th International Telecommunication Networks and Applications Conference (ITNAC) - Wi-Fi Based Device-free Microwave Ghost Imaging Indoor Surveillance System
摘要： In this paper, we propose an Wi-Fi based device-free microwave ghost imaging (GI) indoor surveillance system. Wireless-Fidelity (Wi-Fi) signals originally designed for communication purposes are employed as the incoherent illumination source in the framework of microwave GI. The object reconstruction procedure of microwave GI is modified to fit indoor scenarios where both stationary and moving objects are presented. Numerical simulation validates that the proposed Wi-Fi based microwave GI scheme can effectively isolate indoor targets reflections with different velocities and obtain focused images respectively. Since the proposed system takes the advantage of existing Wi-Fi access points (APs) as its transceivers, it can be regarded as a device-free system and its complexity and operational cost have been significantly reduced.
关键词： device-free,microwave ghost imaging,Wi-Fi,Doppler effect
更新于2025-09-19 17:15:36
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Temporal Ghost Imaging with Wavelength Conversion
摘要： Ghost imaging is a non-direct measurement technique that uses the correlation between multiple probing patterns and the integrated signal measured after transmission (or reflection) through an object. [1] The resolution of the technique is determined by the characteristic length scale of the probing patterns fluctuations and/or the resolution with which they can be measured. Originally demonstrated in the spatial domain to reconstruct images of real physical objects, ghost imaging has been recently extended to the time-domain to measure ultrafast signals at telecom wavelengths [2]. In this work, we experimentally demonstrate ultrafast ghost imaging in the time-domain where the correlated intensities have completely different wavelengths. This wavelength-conversion temporal ghost-imaging scheme exploits fully the benefit of ghost imaging opening up new possibilities for ultrafast imaging in spectral regions where sensitive and/or fast detectors are not available and in particular the mid-infrared or THz range.
关键词： temporal domain,mid-infrared,ultrafast imaging,Ghost imaging,wavelength conversion,THz range
更新于2025-09-12 10:27:22
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Spatial and temporal resolution in entangled ghost imaging
摘要： We show that, when the integration time of the single photon detectors is longer than the correlation time of the biphoton, the attainable spatial resolution in ghost imaging with entangled signal-idler pairs generated in type II spontaneous parametric down conversion is limited by the angular spread of single-frequency-signal-idler pairs. If, however, the detector integration time is shorter than the biphoton correlation time, the transverse k-vectors of different spectral components combine coherently in the image, improving the spatial resolution.
关键词： ghost imaging,spontaneous parametric downconversion,entangled photons,nonclassical correlation,single photon,phase matching
更新于2025-09-11 14:15:04
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Positive and negative correlations in computational ghost imaging for a grayscale object
摘要： Our previous work has studied the positive-negative correlations in computational ghost imaging for a binary object. In this work, we focus on the computational ghost imaging system for a grayscale object. We studied the second-order correlation function of this system, and gave the criterion of the positive and negative correlations. Furthermore, this criterion was verified by using numerical simulations.
关键词： computational ghost imaging,grayscale object,second-order correlation function,positive-negative correlations
更新于2025-09-10 09:29:36
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Single-Shot Temporal Ghost Imaging Based on Orthogonal Frequency-Division Multiplexing
摘要： Temporal ghost imaging (TGI) is a novel signal reconstruction technology, but the multiple measurements requirement restricts its application to periodic signal detection. Here, we propose a single-shot temporal ghost imaging method based on orthogonal frequency division multiplexing (OFDM) to reconstruct a time-varying signal with high temporal resolution. By encoding pre-programmed Hadamard-matrix-based temporal patterns onto the subcarriers of an OFDM signal, we experimentally obtain ghost images of three kinds of signals with a temporal resolution up to 22.5 ns. Moreover, we use the pre-distortion technique to eliminate the damage of orthogonality of the Hadamard matrix caused by the optical fiber dispersion, and high-quality TGI with 3.2-ns temporal resolution is realized by simulation. Due to the high temporal resolution and image quality, the proposed TGI method could be applied for real-time signal detection.
关键词： ghost imaging,optical signal detection,time imaging,Frequency division multiplexing
更新于2025-09-09 09:28:46
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Probability theory in conditional-averaging ghost imaging with thermal light
摘要： In ghost imaging with thermal light (GITL), the bucket signals are analog signals playing the role of weights in the algorithms of image reconstruction. However, diverse bucket signals seemed to be completely ignored in conditional-averaging GITL, which was recently proposed by two groups [Appl. Phys. Lett. 100, 131114 (2012); Chin. Phys. Lett. 29, 074216 (2012)]. Even so, positive and negative ghost images were obtained by averaging just partial reference signals. To understand this effect, one needs to determine the statistical relation between random bucket signals and reference signals. Here, we apply probability theory to GITL by regarding thermal light intensities as stochastic variables, and then deduce the joint probability density function between the bucket and reference signals. Positive and negative images are formed in ensemble averaging of the product of the reference signal and two logic quantities of the bucket signals. The visibility and contrast-to-noise ratio of these images in conditional-averaging GITL are analyzed in detail in both theory and experiment. As for applications, we perform an experiment of remote conditional-averaging GITL and verify that the image quality is maintained when the bucket signals are extremely attenuated. Our method can be applied to any ghost imaging scenarios in which the specific statistics of the optical source is given.
关键词： ghost imaging,visibility,conditional-averaging,probability theory,thermal light,contrast-to-noise ratio
更新于2025-09-09 09:28:46
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Quantum secure ghost imaging
摘要： In this work, we propose a scheme of quantum secure ghost imaging (QSGI), which combines temporal quantum ghost imaging and security test based on quantum entanglement. Utilizing the quantum feature of entangled photon pairs, the eavesdropping in the imaging process can be detected, with a certain degree of protection on the object information. The proposed scheme is demonstrated by experiment, in which photon pairs are generated by a quantum light source based on a silicon waveguide. Two-dimensional patterns are imaged line by line over 50 km optical fibers and the security test is realized by two-photon interference for energy-time entanglement. QSGI could be applied in scenarios of secure imaging and surveillance, and may inspire new ideas on specific quantum communication tasks.
关键词： quantum entanglement,quantum secure ghost imaging,secure imaging,quantum communication
更新于2025-09-04 15:30:14