Elektrik Elektronik Mühendisliği Bölümü Yayın Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/411

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Citation - WoS: 6
Citation - Scopus: 6
Array of Nanoparticles Coupling With Quantum-Dot: Lattice Plasmon Quantum Features
(Elsevier Science Bv, 2018) Salmanogli, Ahmad; Gecim, H. Selcuk
In this study, we analyze the interaction of lattice plasmon with quantum-dot in order to mainly examine the quantum features of the lattice plasmon containing the photonic/plasmonic properties. Despite optical properties of the localized plasmon, the lattice plasmon severely depends on the array geometry, which may influence its quantum features such as uncertainty and the second-order correlation function. To investigate this interaction, we consider a closed system containing an array of the plasmonic nanoparticles and quantum-dot. We analyze this system with full quantum theory by which the array electric far field is quantized and the strength coupling of the quantum-dot array is analytically calculated. Moreover, the system's dynamics are evaluated and studied via the Heisenberg-Langevin equations to attain the system optical modes. We also analytically examine the Purcell factor, which shows the effect of the lattice plasmon on the quantum-dot spontaneous emission. Finally, the lattice plasmon uncertainty and its time evolution of the second-order correlation function at different spatial points are examined. These parameters are dramatically affected by the retarded field effect of the array nanoparticles. We found a severe quantum fluctuation at points where the lattice plasmon occurs, suggesting that the lattice plasmon photons are correlated.
Citation - WoS: 8
Citation - Scopus: 8
Design of Quantum Sensor To Duplicate European Robins Navigational System
(Elsevier Science Sa, 2021) Salmanogli, Ahmad; Gokcen, Dincer
In this article, we design a quantum device to duplicate the European Robins procedure to precisely deter-mine the migratory route. In the mentioned procedure, the important issue is the geomagnetic field effect on the magnetic momentum of the created radical pairs (triplet-singlet states) dancing with a special fre-quency. To duplicate the procedure, a quantum sensor consisting of two coincident tripartite systems is designed. Each tripartite system is independently excited with the entangled photons (signal and idler). The interesting point is that by manipulation of the system in the right condition, the microwave cavities modes separately affected by the entangled photons can be entangled. The entangled microwave photons play the same role as the triplet-singlet states present in the bird's navigational system. The key point in the design of the quantum sensor is that the entanglement between microwave photons can be strongly affected by the external magnetic field. In fact, this is the criterion employed by the quantum sensor to sense the magnetic field intensity and the direction. To analyze the system, the canonical quantization (or microscopic) method is used to determine the sensor's Hamiltonian, and also the system dynamics equations of motions are analytically derived using Heisenberg-Langevin equations. (c) 2021 Elsevier B.V. All rights reserved.
Citation - WoS: 1
Citation - Scopus: 2
Dynamical System Parameter Identification Using Deep Recurrent Cell Networks Which Gated Recurrent Unit and When
(Springer London Ltd, 2021) Akagunduz, Erdem; Cifdaloz, Oguzhan
In this paper, we investigate the parameter identification problem in dynamical systems through a deep learning approach. Focusing mainly on second-order, linear time-invariant dynamical systems, the topic of damping factor identification is studied. By utilizing a six-layer deep neural network with different recurrent cells, namely GRUs, LSTMs or BiLSTMs; and by feeding input/output sequence pairs captured from a dynamical system simulator, we search for an effective deep recurrent architecture in order to resolve the damping factor identification problem. Our study's results show that, although previously not utilized for this task in the literature, bidirectional gated recurrent cells (BiLSTMs) provide better parameter identification results when compared to unidirectional gated recurrent memory cells such as GRUs and LSTM. Thus, indicating that an input/output sequence pair of finite length, collected from a dynamical system and when observed anachronistically, may carry information in both time directions to predict a dynamical systems parameter.
Citation - WoS: 7
Citation - Scopus: 7
Entangled Microwave Photons Generation Using Cryogenic Low Noise Amplifier (Transistor Nonlinearity Effects)
(Iop Publishing Ltd, 2022) Salmanogli, Ahmad
This article mainly focuses on important quantum phenomenon called entanglement arising the nonlinearity property. This study uses a unique approach in which transistor nonlinearity effect (third-order nonlinearity) entangled microwave photons are created in a cryogenic low-noise amplifier (LNA). For entanglement analysis, the Hamiltonian of the designed cryogenic LNA (containing two coupled oscillators) is derived, and then, using the dynamic equation of motion, the oscillator's number of photons and the phase-sensitive cross-correlation factor are calculated in the Fourier domain to calculate the entanglement metric. The oscillators are coupled to each other through the gate-drain capacitor, and nonlinear transconductance is as an important factor strongly manipulating the entanglement. As a main conclusion, the study shows that the designed circuit using transistor third-order nonlinearity has the ability to generate the entangled microwave photons at very low intrinsic transconductance and more importantly when the noise figure (NF) is strongly minimized. As a complementary task, the printed circuit board of the cryogenic LNA is designed and simulated to verify the ability of the circuit to achieve an ultralow NF, by which the probability of the generation of entangled microwave photons is increased.
Entangled Two-Photon Interference
(Elsevier Gmbh, 2019) Salmanogli, Ahmad
This article proposes a theoretical solution to one of the original problems of the double-slit experiment, which expresses that it is impossible to identify the photon's path without disturbing it We contend that using the entangled two-photon (signal and idler photons) and inserting a double-slit into the beam of signal (idler) photon, it is possible to distinguish the path of signal (idler) photon, just by the detection of the idler (signal) photon. Basically, the signal and idler photons are highly correlated to each other due to the momentum conservation. Indeed, the photon-photon correlation originates the nonlocal interference effect, so using this effect, lets us know about which path the photon goes through, with its conjugate photon's position detection rather than its detection.
Citation - WoS: 17
Citation - Scopus: 17
Entanglement Sustainability Improvement Using Optoelectronic Converter in Quantum Radar (Interferometric Object-Sensing)
(Ieee-inst Electrical Electronics Engineers inc, 2021) Salmanogli, Ahmad; Gokcen, Dincer
In this study, the main focus is laid on the design of an optoelectronic converter as a part of the quantum radar to enhance the entanglement between retained and returned modes at high temperatures. The electro-opto-mechanical converter has been widely studied, and the results showed that the operation at high temperature is so crucial to generate and preserve the entanglement between modes. The main problem arises because the mechanical part operating at a low frequency leads to a large number of thermally excited photons, and eventually, the entanglement between modes becomes lost. To solve the problem, we replace the mechanical part with the optoelectronic components. The optical cavity is coupled to the microwave cavity in the newly designed system through a Varactor diode excited by a photodetector. As the main goal, to improve the entanglement sustainability, the effect of the coupling factor of the microwave cavity to photodetector is investigated. The results show that the mentioned factor creates some degrees of freedom to enhance the entanglement at high temperatures compared to the electro-opto-mechanical converter. At some specific values of the coupling factor, the retained and returned fields remained completely entangled up to 5.5 K and partially entangled around 50 K.
Citation - WoS: 6
Citation - Scopus: 7
Optical and Microcavity Modes Entanglement by Means of Plasmonic Opto-Mechanical System
(Ieee-inst Electrical Electronics Engineers inc, 2020) Salmanogli, Ahmad; Gecim, H. Selcuk
In this study, plasmonic opto-mechanical tripartite system is proposed to improve the performance of the traditional tripartite opto-mechanical system. In the new design, significantly, optical cavity and microwave cavity modes are directly coupled to each other. The originality of this work consists in embedding a microsphere in the optical cavity where the plasmon-plasmon interaction between the metal plates generates a plasmon mode inside the optical cavity and changes the electric field distribution. The plasmonic property influences the microsphere electrical properties and interacts with the photonic mode inside the optical cavity by which the microwave cavity properties are also affected through coupling to the optical cavity. Microsphere introduces a capacitor as a function of plasmonic properties that can strongly influence the microwave cavity resonance frequency. That is the feature that we want to utilize to enhance the performance of the system at high temperature. The results show that the optical cavity and microwave cavity modes remain entangled at high temperature. It is contributed to the plasmonic-based capacitor induced by the microsphere which is not affected by the thermally induced photons (noise). It is worth mentioning that the induced noise strongly restricts the traditional tripartite system operated with a wide bandwidth.
Optoelectronic based Quantum Radar: Entanglement Sustainability Improving at High Temperature
(2020) Salmanoğli, Ahmad; Gökçen, Dinçer
Citation - WoS: 5
Citation - Scopus: 5
Plasmonic Effect on Quantum-Dot Photodetector Responsivity
(Ieee-inst Electrical Electronics Engineers inc, 2019) Salmanogli, Ahmad; Gokcen, Dincer; Gecim, H. Selcuk; Selcuk Gecim, H.
In this paper, we analyze and simulate the plasmonic effect on the quantum-dot photodetector responsivity. For this purpose, a plasmonic-based quantum-dot photodetector is designed in which a few quantum dots are embedded in the hot-spot regions of the plasmonic nanoparticles, wherein a high-intensity localized field is created. Notably, due to the maximum overlapping of the plasmonic field with the quantum dots at the hot spot, some of the optical characteristics of the quantum dot, particularly the spontaneous emission decay rate, are changed. This paper focuses on the engineering of the decay rate, through which we found that the quantum-dot photodetector responsivity is strongly enhanced with the order of 100 times at the visible range. For analyzing the proposed system, we first work on the plasmonic effect of the nanoparticle on the quantum-dot lifetime using the Heisenberg-Langevin equations. It is shown that by embedding the quantum dots at the hot spot of the nanoparticle, the decay rate of the quantum dot is dramatically influenced. In the following, plasmonic-quantum dot system responsivity is theoretically examined using a time-varying perturbation theory. Using this approach is necessary because the spontaneous emission cannot be analyzed with the classical methods. Consequently, it is proved that using plasmonic effect leads to enhanced photodetector responsivity, suggesting that even very small incoming signals are detectable.
Citation - WoS: 4
Citation - Scopus: 3
Quantum Correlation of Microwave Two-Mode Squeezed State Generated by Nonlinearity of Inp Hemt
(Nature Portfolio, 2023) Salmanogli, A.
This study significantly concentrates on cryogenic InP HEMT high-frequency circuit analysis using quantum theory to find how the transistor nonlinearity can affect the quantum correlation of the modes generated. Firstly, the total Hamiltonian of the circuit is derived, and the dynamic equation of the motion contributed is examined using the Heisenberg-Langevin equation. Using the nonlinear Hamiltonian, some components are attached to the intrinsic internal circuit of InP HEMT to address the circuit characteristics fully. The components attached are arisen due to the nonlinearity effects. As a result, the theoretical calculations show that the states generated in the circuit are mixed, and no pure state is produced. Accordingly, the modified circuit generates the two-mode squeezed thermal state, which means one can focus on calculating the Gaussian quantum discord to evaluate quantum correlation. It is also found that the nonlinearity factors (addressed as the nonlinear components in the circuit) can intensely influence the squeezed thermal state by which the quantum discord is changed. Finally, as the primary point, it is concluded that although it is possible to enhance the quantum correlation between modes by engineering the nonlinear components; however, attaining quantum discord greater than unity, entangled microwave photons, seems a challenging task since InP HEMT operates at 4.2 K.
Citation - WoS: 4
Citation - Scopus: 6
Scintillation of Laser Beams in Weak Atmospheric Turbulence for Aerial Vehicle in the Use of Lidar
(Ieee-inst Electrical Electronics Engineers inc, 2022) Baykal, Yahya; Gercekcioglu, Hamza
Formulation of on-axis scintillation of laser beams is found in weak atmospheric turbulence for aerial vehicle in the use of light detection and ranging (LIDAR) systems by employing the Rytov method. The formulation derived for collimated Gaussian, plane and spherical beams is evaluated in vertical link involving up/down link. In this medium, the behavior of these beams in terms of deterioration is examined. In this context, the on-axis scintillation index values are plotted versus normalized target size parameter, target size, source size, propagation distance and zenith angle, and the results are obtained for LIDAR systems operating for aerial vehicle in vertical atmospheric link by using ground/space transceiver. The degradation is greater in operating with ground transceiver than in operating with space transceiver. Additionally, while the on-axis scintillation index is minimized in the smaller target size in use of ground transceiver than in use of space transceiver, that is, it can also be minimized in the larger target size in use of space transceiver. The values of source size and the normalized target size parameter minimizing the obtained scintillation index, are 1.2 cm, 10, and 6 cm and 5 for ground transceiver and space transceiver, respectively.
Citation - WoS: 17
Citation - Scopus: 16
Transmittance of Multi Gaussian Optical Beams for Uplink Applications in Atmospheric Turbulence
(Ieee-inst Electrical Electronics Engineers inc, 2015) Ata, Yalcin; Baykal, Yahya
On-axis slant path uplink transmittance (used in short as transmittance throughout the text) for multi Gaussian optical beam in Kolmogorov atmospheric turbulent medium is investigated. It is observed that for both the flat-topped and the annular beams, as the propagation distance, wind speed and the zenith angle increase, the transmittance decreases. The transmittance of flat-topped beams increases when the number of beams, source size or the wavelength increases. For the annular beam, when the outer/inner beam size ratio is kept constant, larger source sizes yield larger transmittance values. Transmittance of the thicker annular beams is found to be larger than the transmittance of the thinner annular beams.

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