Advanced Theory of Instability in Tunneling Nanostructures

This work is concerned with the quantum structure of resonant tunneling diodes, which exhibits intrinsic instability that can be exploited for the development of high-speed, high-frequency devices. The article examines in detail the physics underlying the non-liner instability, in both a one-band model and a multiple-band model. The theoretical basis of the description of electronic processes in such structures are described in some detail in terms of nonequilibrium Green's functions. Also presented here is a semi-phenomenological model of the resonant tunneling diode based on nonlinear circuit theory. Recent works and progresses in this and related areas are summarized here as well.

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Numerical Modelling of a Graphene - Resonant Tunneling Diode as a High Frequency Oscillator

10.14293/s2199-1006.1.sor-.ppjrr4b.v1 ◽

2019 ◽

Author(s):

Shakirudeen Lasisi

Keyword(s):

High Frequency ◽

Resonant Tunneling ◽

High Speed ◽

Hexagonal Boron Nitride ◽

Domain Boundary ◽

Resonant Tunneling Diode ◽

Total Output ◽

High Electron ◽

Tunneling Diode ◽

Output Synchronization

New solid-state sources of Gigahertz-Terahertz electromagnetic radiation continue to have many applications in high-speed electronics, communications, security, and medicine. To develop new devices, it is important to understand the coupling of such high-frequency sources not only with each other but also with their environment e.g. to achieve increased power output, synchronization, and to control interference. Using Graphene-based materials is particularly promising due to its high electron mobility and configurability of the device structures. However, accurately modelling its electromagnetic behavior computationally along with the inherent complexities of the device itself (e.g. non-linearities, and quantum effects) can be quite challenging using current tools. To address this, we use a simplified approximate model to reduce the complexity of the structure and derive new formulations that describe its electromagnetic and intrinsic behaviours. In this poster, we report new formulations, finite element spaces and general progress in modelling a graphene hexagonal-boron-nitride resonant tunneling diode (GRTD) using the time-domain boundary element method. We also explore the possibility of mutual coupling and synchronization between two GRTD devices as well as their radiation patterns and total output power.

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The Design and Testing of Mesopiezoresistive Effect Electromagnetic Driven Micromachined Gyroscope

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.139-141.1566 ◽

2010 ◽

Vol 139-141 ◽

pp. 1566-1569

Author(s):

Rui Rong Wang ◽

Kang Du ◽

Yun Bo Shi ◽

Jun Liu

Keyword(s):

Resonant Tunneling ◽

High Speed ◽

Low Voltage ◽

Negative Resistance ◽

Process Technology ◽

Tunneling Diodes ◽

Tunneling Diode ◽

Current Voltage ◽

Micromachined Gyroscope ◽

Design And Testing

Resonant tunneling diode (RTD) is a bipolar negative resistance device with the features of high speed, high frequency, low voltage and power, has been proved to have mesopiezoresistive effect, and the current-voltage characteristics of RTD is a function of stress. In the paper, the mesopiezoresistive effect of resonant tunneling diodes and Coriollis effect are both used in the research of gyroscope, so a novel gyroscope structure is proposed. The feasible fabrication process is designed according to present process technology, and the gyroscope is fabricated by GaAs surface micromachining processes and bulk micromachining technology. By the driven experiment it is verify that the gyroscope can be successfully driven. And the range of fabricated gyroscope natural frequency is also obtained, which is larger than 4KHz.

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