Scopus İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8651
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Article Citation - WoS: 4Citation - Scopus: 5Accurate Method To Calculate Noise Figure in a Low Noise Amplifier: Quantum Theory Analysis(Elsevier Sci Ltd, 2022) Salmanogli, Ahmad; Gecim, H. SelcukIn this study, a low-noise amplifier is quantum-mechanically analyzed to study the behavior of the noise figure. The analysis view has been changed from classic to quantum, because using quantum theory produces some degrees of freedom, which may be ignored when a circuit is analyzed using classical theory. For this purpose, the Lagrangian is initially derived by considering the related nonlinearity of the transistor, and then using the Legendre transformation and canonical quantization procedure, the quantum Hamiltonian is derived. As an interesting point of this study, the low-noise amplifier is deliberately considered as two oscillators connecting to each other to share the photonic modes between them; accordingly, the voltage and current as measurable observations and the noise figure as a critical quantity in a low-noise amplifier are theoretically expressed in terms of the oscillator's mean photon number. The main goal of this work is to study quantities such as the noise figure in a sufficient detail using quantum theory. In addition, as an advantage of this theory, one can control and manipulate the noise figure only by manipulation of the oscillator's mean photon number and coupling it between two oscillators. Finally, the circuit is classically designed and simulated to verify the derived results using quantum theory. The comparison results show that there is a partial consistency between the two approaches; as the frequency increases, the noise figure becomes minimized at a particular frequency.Article Quantum Dot Transition Rate Modifying by Coupling To Lattice Plasmon(Springer, 2023) Salmanogli, Ahmad; Gecim, H. Selcuk; Hatem, SudeIn this study, a plasmonic system coupled to a quantum dot is defined to generate the entanglement between two non-simultaneous emitted output modes. The quantum dot with three energy levels creates two different transition rates by which non-simultaneous photons are emitted. Thus, it seems that the entanglement between two emitted modes is forbidden. However, the simulation results show the entanglement between the output modes. It is because the original transition rates of the quantum dot are modified due to the lattice plasmon coupling effect. It means that the effective transition rate affected by the lattice plasmon plays a key role. The lattice plasmon coupling to quantum dot at some locations leads to a simultaneous transition by which the entanglement between output modes is established. The entangled output modes refer to the entangled photons with a specific frequency (e.g., the emission frequency). This unique behavior is theoretically discussed and the results show that using the lattice plasmon can change the transition rates by which the two emitted modes become entangled.Article Citation - WoS: 1Citation - Scopus: 2Entangled State Engineering in the 4-Coupled Qubits System(Elsevier, 2023) Salmanogli, AhmadThis article studies the behavior of the avoided level crossing in the 4-coupled qubit to each other and mainly focuses on how to engineer it. This phenomenon occurs due to the two transitions out of the ground state in a two-coupled qubit, contributing to the entangled states. This essential and unique behavior can be engineered in a quantum circuit. For this reason, a quantum circuit containing 4 qubits is designed, and its quantum Hamiltonian and dynamic equation of the motion are theoretically derived. Analysis of the entanglement between each coupled qubit using the entanglement metric reveals that the strength of the qubit-qubit coupling factor and the qubit's non-linearity play an essential role in engineering the photonic mode entanglement. The results show that the avoided level crossing appears in the photonic mode entanglement. In other words, two or more transitions from the ground state to the multiple excited states for each bias current. However, the interesting point is that the avoided level crossing just occurs for the qubits connected capacitively to the driven field (the first qubit in this work), not for all.& COPY; 2023 Elsevier B.V. All rights reserved.Article Citation - WoS: 1Citation - Scopus: 1Enhancing Quantum Correlation at Zero-If Band by Confining the Thermally Excited Photons: Inp Hemt Circuitry Effect(Springer, 2023) Salmanogli, AhmadThe microwave quantum correlation as a crucial issue in quantum technology is analyzed and studied. An open quantum system operating at 4.2 K is designed in which InP HEMT as the nonlinear component couples two external oscillators. The quantum theory is applied to analyze the system completely. The Lindblad Master equation is used to analyze the time evolution of the expanded closed system that covers the environmental effects. In the following, the state of the system defined is determined in terms of the ensemble average state using the density matrix; then, the ensemble average of the different operators is calculated. Accordingly, the covariance matrix of the quantum system is derived, and the quantum discord as a key quantity to determine the quantum correlation is calculated. As an interesting point, the results show that InP HEMT mixes two coupling oscillator modes so that the quantum correlation is created at different frequency productions, especially the zero-IF band. Nonetheless, the main point is that one can strongly manipulate the quantum correlation in the zero-IF using circuitry engineering. It is established by increasing the operational frequencies in the quantum system leading to dramatically limiting the thermal noise since the zero-IF band remains unchanged.Article Citation - WoS: 5Citation - Scopus: 5Raman Mode Non-Classicality Through Entangled Photon Coupling To Plasmonic Modes(Optical Soc Amer, 2018) Salmanogli, AhmadIn this article, non-classical properties of Raman modes are investigated. The original goal, actually, is to identify how and by which method we can induce non-classicality in Raman modes. We introduce a plasmonic system in which Raman dye molecules are buried between two shells of the plasmonic materials, similar to an onionlike core/shell nanoparticle. This system is excited by the entangled two-photon wave, followed by analysis of its dynamics of motion using the Heisenberg-Langevin equations by which the time evolution of the signalidler mode and Raman modes are derived. Interestingly, the entangled two-photon wave is coupled to the plasmonic modes, which are used to improve the non-classicality. It is shown that the exciting system with the entangled photons leads to inducing the non-classicality in Raman modes and entanglement between them. Moreover, it is seen that the plasmon-plasmon interaction in the gap region has a strong effect on the non-classicality of the input modes and also affects entangling of the Raman modes, which means that plasmonic modes generated by the core/shell nanoparticles manipulate the Raman modes' quantum properties. It is shown that the quantum properties in the designed system are dramatically influenced by the environmental temperature and the location of the Raman molecules in the gap region. The modeling results demonstrate that by changing the location of the Raman molecules, the non-classicality of the Raman modes and their entanglement are altered. Finally, as an important result, it is revealed that the Raman modes, such as the Stokes and anti-Stokes modes, show a revival behavior, which is a quantum phenomenon. (c) 2018 Optical Society of America.Article Citation - WoS: 10Citation - Scopus: 10Modification of a Plasmonic Nanoparticle Lifetime by Coupled Quantum Dots(Amer Physical Soc, 2019) Salmanogli, AhmadIn this study, the interaction between a plasmonic nanoparticle and coupled quantum dots is investigated to identify how the coupled particles can manipulate the plasmonic nanoparticle decay rate. This subject is very important, because most applications of the plasmonic system are restricted due to the nanoparticle decay rate and the related losses. Therefore, in the present work, we try to find out how and by which method the plasmonic nanoparticle decay rate can be manipulated. For this purpose, a plasmonic system containing a nanoparticle coupled to some small quantum dots is designed. The system dynamics of motions are analyzed with Heisenberg-Langevin equations. These equations are analyzed to study the effect of the plasmonic nanoparticles on the quantum dots' decay rate. In the following, as an interesting point, the quantum dot coupling influence on the nanoparticle's decay rate is theoretically analyzed in the transient and steady-state conditions. Additionally, a theoretical formula is derived by which one can explicitly find the dependency of the modified decay rate of the plasmonic nanoparticle on the number of the coupled quantum dots and the coupling strength. The simulation results show that it is possible to effectively control the nanoparticles' decay rate with regard to the application for which they are utilized.
