The single-photon isolator is in high demand for optical communications and optical information processing in the quantum regime, but the noise is still a limitation. Here, the author theoretically propose a noiseless...
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The single-photon isolator is in high demand for optical communications and optical information processing in the quantum regime, but the noise is still a limitation. Here, the author theoretically propose a noiseless single-photon isolator scheme and demonstrate experimentally using hot atoms. Nonreciprocal devices, such as isolators, are of great importance for optical communication and optical information processing. To bypass the limitation of a strong magnetic field imposed by the traditional Faraday magneto-optic effect, many alternative mechanisms have been proposed to demonstrate magnetic-free nonreciprocity. However, limited by the drive-induced noise, the noiseless isolator capable of working in the quantum regime has yet to be realized in the experiment. Here, we show a noiseless all-optical isolator with genuine single photons in hot atoms. We experimentally study this mechanism using an open V-type level scheme and demonstrate a low insertion loss of 0.6 dB and high isolation of 30.3 dB with bandwidth up to hundreds of megahertz. Furthermore, the nonreciprocal direction can be truly reversed only by tuning the frequency of the pump laser with the same setup. Our scheme relies on widely used optical technology and is thus universal and robust.
This paper demonstrates a novel optical-cryptographic system based on a new image self-disordering algorithm (ISDA). The cryptographic stage is based on an iterative procedure using an ordering sequence from the input...
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This paper demonstrates a novel optical-cryptographic system based on a new image self-disordering algorithm (ISDA). The cryptographic stage is based on an iterative procedure using an ordering sequence from the input data to produce diffusion and confusion keys. Our system uses this approach over plaintext and optical cipher from a 2f-coherent processor working with two random phase masks. Since the keys used for encryption depend on the initial input information, the system is resistant to common attacks such as the chosen-plaintext attack (CPA) and the known-plaintext attack (KPA). In addition, since the ISDA operates the optical cipher, the 2f processor linearity is destroyed, producing an enhanced ciphertext in phase and amplitude, improving optical encryption protection. This new approach offers higher security and efficiency than other reported systems. We perform security analyses and validate the feasibility of this proposal by synthesizing an experimental keystream and performing color image encryption.(c) 2023 Optica Publishing Group
The results of an investigation that focused on the development of an adjustable image contrast method are presented. The method was designed to solve the applied problem of measuring the concentration of contaminatio...
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The results of an investigation that focused on the development of an adjustable image contrast method are presented. The method was designed to solve the applied problem of measuring the concentration of contamination of recoverable scrap with cutting fluid to enhance the accuracy of visual inspection methods. The currently used control method is based on visual assessment of the degree of contamination of a sheet of paper after its contact with a sample of contaminated material. The proposed method entails the use of a standard image scanner for digitizing visual information in the form of oil imprints on the paper and its subsequent processing by adjusting the image contrast, which makes it possible to obtain quantitative information on the object under investigation. The principal parameters of oil imprint scanning and subsequent processing of the obtained images were determined during the course of the study. Equations for calculating the values of reduction of cutting fluid content in the cleaned samples with respect to its initial concentration were obtained. The main concepts of the proposed method were formulated. Its main advantage is its simplicity and the use of commonly available, inexpensive control and measuring equipment. (C) 2021 Optica Publishing Group
The all-optical/optoelectronic hybrid intelligent computing with high speed and low power consumption characteristics has emerged as a promising solution for the bottleneck of Moore's Law. However, the low deploym...
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We propose and experimentally demonstrate a magnetic field free isolator based on the light shift effect in miniaturized hot vapor cell. This work paves the way into nonmagnetic optical isolator for optical informatio...
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In an effort to establish a standardized method for measuring complex three-dimensional parts manufactured using additive manufacturing, this case study measure true position and cylindricity deviations in a recently ...
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The existing tomographic radiation thermometry method based on multi-view optical imaging is not applicable to the closed combustion environments due to light obstruction induced by burner wall. To solve the problem o...
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The paper presents a study aimed at optimizing the reading and evaluating process of multiple-choice exam sheets (optical forms) as a smart campus application at Izmir Bakircay University, significantly reducing the t...
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The rapid advancement of optical computing chips has promoted the development of optical communications. However, current on-chip systems usually depend on specialized optical structures for computing functions, which...
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Multi-plane light converters (MPLCs) are an emerging class of optical devices capable of converting a set of input spatial light modes to a new target set of output modes. This operation represents a linear optical tr...
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Multi-plane light converters (MPLCs) are an emerging class of optical devices capable of converting a set of input spatial light modes to a new target set of output modes. This operation represents a linear optical transformation-a much sought after capability in photonics. MPLCs have potential applications in both the classical and quantum optics domains, in fields ranging from optical communications to optical computing and imaging. They consist of a series of diffractive optical elements (the "planes"), typically separated by a free space. The phase delays imparted by each plane are determined by the process of inverse-design, most often using an adjoint algorithm known as the wavefront matching method (WMM), which optimizes the correlation between the target and actual MPLC outputs. In this work, we investigate high mode capacity MPLCs to create arbitrary spatial mode sorters and linear optical circuits. We focus on designs possessing low numbers of phase planes to render these MPLCs experimentally feasible. To best control light in this scenario, we develop a new inverse-design algorithm, based on gradient ascent with a specifically tailored objective function, and show how, in the low-plane limit, it converges to MPLC designs with a substantially lower modal cross-talk and higher fidelity than those achievable using the WMM. We experimentally demonstrate several prototype few-plane high-dimensional spatial mode sorters, operating on up to 55 modes, capable of sorting photons based on their Zernike mode or orbital angular momentum state, or an arbitrarily randomized spatial mode basis. We discuss the advantages and drawbacks of these proof-of-principle prototypes and describe future improvements. Our work points to a bright future for high-dimensional MPLC-based technologies. (c) 2023 Author(s).
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