Impact of Temperature Variation on Performance of Carbon Nanotube Field-Effect Transistor-Based on Chaotic Oscillator:A Quantum Simulation Study

We evaluate the impact of temperature on the output behavior of a carbon nanotube field effect transistor （CNFET） based chaotic generator. The sources cause the variations in both current-voltage characteristics of the CNFET device and an overall chaotic circuit is pointed out. To verify the effect of temperature variation on the output dynamics of the chaotic circuit, a simulation is performed by employing the CNFET compact model of Wong et al. in HSPICE with a temperature range from -100℃ to 100℃. The obtained results with time series, frequency spectra, and bifurcation diagram from the simulation demonstrate that temperature plays a significant role in the output dynamics of the CNFET-based chaotic circuit. Thus, temperature-related issues should be taken into account while designing a high-quality chaotic generator with high stability.

A voltage-controlled chaotic oscillator based on carbon nanotube field-effect transistor for low-power embedded systems

This paper presents a compact and low-power-based discrete-time chaotic oscillator based on a carbon nanotube field-effect transistor implemented using Wong and Deng＇s well-known model. The chaotic circuit is composed of a nonlinear circuit that creates an adjustable chaos map, two sample and hold cells for capture and delay functions, and a voltage shifter that works as a buffer and adjusts the output voltage for feedback. The operation of the chaotic circuit is verified with the SPICE software package, which uses a supply voltage of 0.9 V at a frequency of 20 kHz. The time series, frequency spectra, transitions in phase space, sensitivity with the initial condition diagrams, and bifurcation phenomena are presented. The main advantage of this circuit is that its chaotic signal can be generated while dissipating approximately 7.8 μW of power, making it suitable for embedded systems where many chaos-signal generators are required on a single chip.

Photodiode-Based Chua＇s Circuit with Light Controllability

我们由光是可控制的现在的基于光电二极管的 Chua 的混乱电路。建议电路与否定非线性由一个电感器，二个被动电容器，一个基于光电二极管的可变电阻器，和积极反馈跨导体组成。电路的混乱动力学被用 0.35m 与集成电路强调分析使用模拟程序验证互补 metal-oxide-semiconductor 过程参数。获得结果(例如时间波形，频率分析，三维的引起注意的人，分叉和 Lyapunov 代表图) 证实电路的混乱行为能被轻紧张经由基于光电二极管的可变电阻器控制。

Bifurcation Analysis of the Voltage Controlled Photosensitive Chaotic Oscillator

A photosensitive chaotic oscillator which can be controlled with light illumination under various control voltage levels is proposed.The oscillator consists of a photodiode for the light input,clock switches and capacitors for the sample and hold function,a nonlinear function that creates an adjustable chaos map,and a voltage shifter that adjusts the output voltage for feedback.After optimizing the photodiode sub-circuit by using an available photodiode model in PC-based simulation program with integrated circuit emphasis to obtain a suitable output,the full chaotic circuit is verified with standard 0.6-μm complementary metal oxide semiconductor parameters.Chaotic dynamics are analyzed as a function of the light intensity under different control voltage levels.The time series,frequency spectra,transitions in state spaces,bifurcation diagrams and the largest Lyapunov exponent are improved.

Effect of Temperature on a Two-Phase Clock-Driven Discrete-Time Chaotic Circuit

The effects of temperature on a two-phase clock-driven discrete-time chaotic circuit are presented.The circuit for temperature analysis consists of two switches for sample and hold,a source follower,and a nonlinear function for nonlinearity in the feedback.The chaotic dynamics of this circuit,such as time series,state transitions,frequency spectra bifurcation diagrams and Lyapunov exponents are analyzed as functions of the temperature.It is confirmed that the dynamics of the chaotic circuit have a temperature dependence.Further,we find that the circuit can generate discrete chaotic signals only within specific temperature regions.

Stability of operation versus temperature of a three-phase clock-driven chaotic circuit

We evaluate the influence of temperature on the behavior of a three-phase clock-driven metal–oxide–semiconductor （MOS） chaotic circuit. The chaotic circuit consists of two nonlinear functions, a level shifter, and three sample and hold blocks. It is necessary to analyze a CMOS-based chaotic circuit with respect to variation in temperature for stability because the circuit is sensitive to the behavior of the circuit design parameters. The temperature dependence of the proposed chaotic circuit is investigated via the simulation program with integrated circuit emphasis （SPICE） using 0.6-μm CMOS process technology with a 5-V power supply and a 20-kHz clock frequency. The simulation results demonstrate the effects of temperature on the chaotic dynamics of the proposed chaotic circuit. The time series, frequency spectra, bifurcation phenomena, and Lyapunov exponent results are provided.