Publications by authors named "A Hatziefremidis"

In the last ten years, silicon photonics has made considerable strides in terms of device functionality, performance, and circuit integration for a variety of practical uses, including communication, sensing, and information processing. In this work, we theoretically demonstrate a complete family of all-optical logic gates (AOLGs), including XOR, AND, OR, NOT, NOR, NAND, and XNOR, through finite-difference-time-domain simulations using compact silicon-on-silica optical waveguides that operate at 1.55 μm.

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In this study, a nonlinear, spring-based finite element approach is employed in order to predict the nonlinear mechanical response of graphyne structures under shear loading. Based on Morse potential functions, suitable nonlinear spring finite elements are formulated simulating the interatomic interactions of different graphyne types. Specifically, the four well-known types of γ-graphyne, i.

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The recent advancements in the fields of artificial intelligence (AI) and machine learning (ML) have affected several research fields, leading to improvements that could not have been possible with conventional optimization techniques. Among the sectors where AI/ML enables a plethora of opportunities, industrial manufacturing can expect significant gains from the increased process automation. At the same time, the introduction of the Industrial Internet of Things (IIoT), providing improved wireless connectivity for real-time manufacturing data collection and processing, has resulted in the culmination of the fourth industrial revolution, also known as Industry 4.

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We present an actively mode-locked fiber ring laser that uses a single active semiconductor optical amplifier device to provide both gain and gain modulation from an external optical pulse train. The laser source generated 4.3-ps pulses at 20 GHz over a 16-nm tuning range and is stable against environmental changes and simple to build.

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Repetition-rate multiplication has been shown by use of a fiber ring oscillator with a semiconductor optical amplifier as the gain medium and by use of fast saturation and recovery of the amplifier from an external optical pulse train. Repetition-frequency multiplication up to 6 times and up to 34.68-GHz frequency have been achieved.

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