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Introduction to Optical, Infrared, and Terahertz Frequency Bands
Published in Song Sun, Wei Tan, Su-Huai Wei, Emergent Micro- and Nanomaterials for Optical, Infrared, and Terahertz Applications, 2023
Song Sun, Wei Tan, Su-Huai Wei
The second type is the electronic terahertz source, which can be further divided into two sub-types: vacuum electronic and solid-state electronic sources. For the former type, travelling wave tube (e.g., backward wave oscillator, extended-interaction klystron oscillator) is commonly used to amplify electromagnetic signal from microwave to terahertz regimes. Other than that, vacuum particle accelerators (e.g., gyrotron, synchrotron, free electron laser) could also generate a broadband electromagnetic wave including terahertz band. The main advantage of vacuum electronic source is the high terahertz output power, but at a cost of bulky and expensive equipment. For the latter type, semiconductor diodes (e.g., Schottky-barrier diode) and transistors (e.g., BiCMOS, HEMT) are widely used for frequency multiplication up to the THz regime, and negative differential resistance devices (e.g., Gunn diode, resonant-tunneling diode) are employed as THz oscillators for direct THz wave generation. Up to date, the multiplier based on Schottky-barrier diode can operated at the frequencies up to ˜ 3 THz, while the oscillator based on resonant-tunneling diode can generate THz wave up to ˜ 2 THz. Recently, a novel solid-state terahertz source based on layered superconductor Bi2Sr2CaCu2O8 was developed. The advantage of solid-state electronic source relies on its high compactness and high integration level.
Fundamentals
Published in Carl Stephen Clifton, Data Communications, 2020
Semiconductors are neither effective conductors nor effective insulators. The two most commonly used semiconductors are germanium and silicon. Silicon has four electrons in the outer shell. This arrangement is conducive of crystal lattice structures that are very regular. Introducing impurities with five electrons in the outer shell produces N-type silicon. So called, because of the appearance or over abundance of negatively charged electrons. Introducing impurities with three electrons in the other shell produces P-type silicon which has an absence of an electron or in effect a "hole.'" Combining the N- and P-type silicon together in various patterns yields diodes, transistors, and other circuits which now perform the functions that electron tubes used to perform. These solid silicon crystal structures are called integrated circuits (ICs) or solid state electronic circuits.
Transistors
Published in Amir M. Sodagar, Analysis of Bipolar and CMOS Amplifiers, 2018
After less than 60 years since the invention of the first transistor, it is horrible to even imagine what will happen if all the transistors in the world suddenly refuse to work. Computers and computerized systems, medical equipment, transportation, navigation systems, communication systems, security systems, and so many other aspects of daily activities are affected by solid-state electronic circuits that involve devices called transistors.
100 Years of the Ubiquitous Traffic Lights: An All-Round Review
Published in IETE Technical Review, 2023
Ashish R. Kulkarni, Narendra Kumar, K. Ramachandra Rao
As such, a review of traffic signals and their evolution is desirable. The evolution of traffic lights (the term “traffic signal(s)” is used interchangeably) in terms of hardware changes and changes in the control algorithm need to be studied. Such a review offers multi-fold advantages – one is the historical perspective; the other is the amalgamation of new techniques or their adoption to a genre for which it was not designed. A case in point can be the evolution of solid-state electronics, microprocessors, computing/computers, evolutionary algorithms, various computing schemes, etc. They have found a place or application in the implementation of traffic signals. Normally, field implementation follows the technological evolution closely. Advances in communication technologies can give an additional boost to implementing integrated city-wide coordinated traffic control solutions. Also, they enhance the capabilities of the existing system and add new dimensions. Since urban spaces are limited, the focus is on capacity management and not on capacity enhancement [8–11].
Electric discharge synthesis of nickel nanoparticles with virtual instrument control
Published in Instrumentation Science & Technology, 2021
Rogelio Ramos, Benjamin Valdez, Nicola Nedev, Mario Curiel, Oscar Perez, Jorge Salvador
Figure 1 shows a schematic representation of a lab-made system used for nanoparticle synthesis, which consists of three main components. The first includes a computer, computing algorithms and a system for data acquisition and control. Together, these three elements form the virtual instrument. The second component serves for amplification and conditioning of the output signals for solid-state electronics and mechanical actuators as well as for measurement of the short circuit voltage (Vsc) that is used to determine the contact between the electrodes. In addition, the second component includes an electronic trigger actuator that provides current and voltage to the electrodes for formation of the controlled arc discharge. The third component is the electromechanical system, which includes a variable voltage power supply and an electro-mechanism for anode displacement and control of the gap between the electrodes.
Influence of ion doping temperature on the distribution of dopant
Published in Radiation Effects and Defects in Solids, 2020
Currently, the development of new and improvement of traditional solid-state electronics devices is an actual problem (1–5). When solving these problems, both the technological processes used for the manufacture of the above devices and the characteristics of the already manufactured devices attracted an interest. In this paper, we analyzed the redistribution of dopant and radiation defects during ion doping of materials at different values of temperatures. The main aim of the paper is analysis of the influence of variation of temperature on the considered redistribution. The accompanying aim of the present paper is the introduction of an analytical approach has been developed for the prognosis of mass and heat transfer with account nonlinearity of these processes and at the same time simultaneous changing of these parameters in space and time.