A logic gate is a device that performs a Boolean function, a logical operation performed on one or more binary inputs that produces a single binary output. Depending on the context, the term may refer to an ideal logic gate, one that has, for instance, zero rise time and unlimited fan-out, or it may refer to a non-ideal physical device.
Digital electronics is a field of electronics involving the study of digital signals and the engineering of devices that use or produce them. This is in contrast to analog electronics which work primarily with analog signals. Despite the name, digital electronics designs includes important analog design considerations.
Dynamic random-access memory is a type of random-access semiconductor memory that stores each bit of data in a memory cell, usually consisting of a tiny capacitor and a transistor, both typically based on metal–oxide–semiconductor (MOS) technology. While most DRAM memory cell designs use a capacitor and transistor, some only use two transistors. In the designs where a capacitor is used, the capacitor can either be charged or discharged; these two states are taken to represent the two values of a bit, conventionally called 0 and 1. The electric charge on the capacitors gradually leaks away; without intervention the data on the capacitor would soon be lost. To prevent this, DRAM requires an external memory refresh circuit which periodically rewrites the data in the capacitors, restoring them to their original charge. This refresh process is the defining characteristic of dynamic random-access memory, in contrast to static random-access memory (SRAM) which does not require data to be refreshed. Unlike flash memory, DRAM is volatile memory, since it loses its data quickly when power is removed. However, DRAM does exhibit limited data remanence.
In automata theory, sequential logic is a type of logic circuit whose output depends on the present value of its input signals and on the sequence of past inputs, the input history. This is in contrast to combinational logic, whose output is a function of only the present input. That is, sequential logic has state (memory) while combinational logic does not.
Theoretical computer science is a subfield of computer science and mathematics that focuses on the abstract and mathematical foundations of computation.
Direct digital synthesis (DDS) is a method employed by frequency synthesizers used for creating arbitrary waveforms from a single, fixed-frequency reference clock. DDS is used in applications such as signal generation, local oscillators in communication systems, function generators, mixers, modulators, sound synthesizers and as part of a digital phase-locked loop.
Reversible computing is any model of computation where the computational process, to some extent, is time-reversible. In a model of computation that uses deterministic transitions from one state of the abstract machine to another, a necessary condition for reversibility is that the relation of the mapping from states to their successors must be one-to-one. Reversible computing is a form of unconventional computing.
The primary focus of this article is asynchronous control in digital electronic systems. In a synchronous system, operations are coordinated by one, or more, centralized clock signals. An asynchronous system, in contrast, has no global clock. Asynchronous systems do not depend on strict arrival times of signals or messages for reliable operation. Coordination is achieved using event-driven architecture triggered by network packet arrival, changes (transitions) of signals, handshake protocols, and other methods.
Quantum dot cellular automata are a proposed improvement on conventional computer design (CMOS), which have been devised in analogy to conventional models of cellular automata introduced by John von Neumann.
A quantum cellular automaton (QCA) is an abstract model of quantum computation, devised in analogy to conventional models of cellular automata introduced by John von Neumann. The same name may also refer to quantum dot cellular automata, which are a proposed physical implementation of "classical" cellular automata by exploiting quantum mechanical phenomena. QCA have attracted a lot of attention as a result of its extremely small feature size and its ultra-low power consumption, making it one candidate for replacing CMOS technology.
Mark A. Horowitz is an American electrical engineer, computer scientist, inventor, and entrepreneur who is the Yahoo! Founders Professor in the School of Engineering and the Fortinet Founders Chair of the Department of Electrical Engineering at Stanford University. He holds a joint appointment in the Electrical Engineering and Computer Science departments and previously served as the Chair of the Electrical Engineering department from 2008 to 2012. He is a co-founder, the former chairman, and the former chief scientist of Rambus Inc.. Horowitz has authored over 700 published conference and research papers and is among the most highly-cited computer architects of all time. He is a prolific inventor and holds 374 patents as of 2023.
Evelyn L. Hu is the Tarr-Coyne Professor of Applied Physics and of Electrical Engineering at Harvard University. Hu has made major contributions to nanotechnology by designing and creating complex nanostructures. Her work has focused on nanoscale devices made from compound semiconductors and on novel devices made by integrating various materials, both organic and inorganic. She has also created nanophotonic structures that might someday facilitate quantum computing.
A reversible cellular automaton is a cellular automaton in which every configuration has a unique predecessor. That is, it is a regular grid of cells, each containing a state drawn from a finite set of states, with a rule for updating all cells simultaneously based on the states of their neighbors, such that the previous state of any cell before an update can be determined uniquely from the updated states of all the cells. The time-reversed dynamics of a reversible cellular automaton can always be described by another cellular automaton rule, possibly on a much larger neighborhood.
Kang Lung Wang is recognized as the discoverer of chiral Majorana fermions by IUPAP. Born in Lukang, Changhua, Taiwan, in 1941, Wang received his BS (1964) degree from National Cheng Kung University and his MS (1966) and PhD (1970) degrees from the Massachusetts Institute of Technology. In 1970 to 1972 he was the Assistant Professor at MIT. From 1972 to 1979, he worked at the General Electric Corporate Research and Development Center as a physicist/engineer. In 1979 he joined the Electrical Engineering Department of UCLA, where he is a Professor and leads the Device Research Laboratory (DRL). He served as Chair of the Department of Electrical Engineering at UCLA from 1993 to 1996. His research activities include semiconductor nano devices, and nanotechnology; self-assembly growth of quantum structures and cooperative assembly of quantum dot arrays Si-based Molecular Beam Epitaxy, quantum structures and devices; Nano-epitaxy of hetero-structures; Spintronics materials and devices; Electron spin and coherence properties of SiGe and InAs quantum structures for implementation of spin-based quantum information; microwave devices. He was the inventor of strained layer MOSFET, quantum SRAM cell, and band-aligned superlattices. He holds 45 patents and published over 700 papers. He is a passionate teacher and has mentored hundreds of students, including MS and PhD candidates. Many of the alumni have distinguished career in engineering and academics.
Gerhard Klimeck is a German-American scientist and author in the field of nanotechnology. He is a professor of Electrical and Computer Engineering at Purdue University School of Electrical and Computer Engineering.
Eby G. Friedman is an electrical engineer, and Distinguished Professor of Electrical and Computer Engineering at the University of Rochester. Friedman is also a visiting professor at the Technion - Israel Institute of Technology. He is a Senior Fulbright Fellow and a Fellow of the IEEE.
David J. Love is an American professor of engineering at Purdue University. He has made numerous contributions to wireless communications, signal processing, information theory, and coding. Much of his research has centered on understanding how feedback and other forms of side information can be utilized during communication.
This glossary of nanotechnology is a list of definitions of terms and concepts relevant to nanotechnology, its sub-disciplines, and related fields.
Paul R. Berger is a professor in electrical and computer engineering at Ohio State University and physics, and a distinguished visiting professor (Docent) at Tampere University in Finland, recognized for his work on self-assembled quantum dots under strained-layer epitaxy, quantum tunneling based semiconductor devices and solution processable flexible electronics.
Supriyo Bandyopadhyay is an Indian-born American electrical engineer, academic and researcher. He is Commonwealth Professor of Electrical and Computer Engineering at Virginia Commonwealth University, where he directs the Quantum Device Laboratory.