A5013330172- Quantum and electron transport phenomena
- Molecular Junctions and Nanostructures
- Advancements in Semiconductor Devices and Circuit Design
- Magnetic properties of thin films
- Advanced Memory and Neural Computing
- Semiconductor Quantum Structures and Devices
- Semiconductor materials and devices
- Quantum Computing Algorithms and Architecture
- Surface and Thin Film Phenomena
- Acoustic Wave Resonator Technologies
- Physics of Superconductivity and Magnetism
- Graphene research and applications
- Force Microscopy Techniques and Applications
- Quantum-Dot Cellular Automata
- Carbon Nanotubes in Composites
- Ferroelectric and Negative Capacitance Devices
- Advanced Semiconductor Detectors and Materials
- Advanced Physical and Chemical Molecular Interactions
- Neural Networks and Applications
- Advanced Thermodynamics and Statistical Mechanics
- Electron and X-Ray Spectroscopy Techniques
- Mechanical and Optical Resonators
- Advanced MEMS and NEMS Technologies
- Quantum Dots Synthesis And Properties
- Chalcogenide Semiconductor Thin Films
Purdue University West Lafayette
2016-2025
Georgia Institute of Technology
2024
Spintronics Research Network of Japan
2020
Tohoku University
2020
Institute of Nanotechnology
2016
Purdue University System
1997-2015
University of California, Berkeley
2009
Zero to Three
2008
Purdue University Northwest
2005
University of California, San Diego
2003
We propose an electron wave analog of the electro-optic light modulator. The current modulation in proposed structure arises from spin precession due to spin-orbit coupling narrow-gap semiconductors, while magnetized contacts are used preferentially inject and detect specific orientations. This may exhibit significant despite multiple modes, elevated temperatures, or a large applied bias.
It is well-known that conventional field effect transistors (FETs) require a change in the channel potential of at least 60 mV 300 K to current by factor 10, and this minimum subthreshold slope S puts fundamental lower limit on operating voltage hence power dissipation standard FET-based switches. Here, we suggest replacing insulator with ferroelectric right thickness it should be possible implement step-up transformer will amplify gate thus leading values than mV/decade enabling low...
Numerical simulations are used to guide the development of a simple analytical theory for ballistic field-effect transistors. When two-dimensional (2-D) electrostatic effects small (and when insulator capacitance is much less than semiconductor (quantum) capacitance), model reduces Natori's MOSFET. The also treats 2-D electrostatics and quantum limit where capacitance. This new provides insights into performance MOSFETs near scaling unified framework assessing comparing variety novel
This paper presents a comparison of the theoretical and experimental current-voltage (I-V) characteristics self-assembled monolayer $\ensuremath{\alpha},{\ensuremath{\alpha}}^{\ensuremath{'}}\ensuremath{-}\mathrm{x}\mathrm{y}\mathrm{l}\mathrm{y}\mathrm{l}$ dithiol molecules on gold substrate measured with scanning tunneling microscope probe. Good quantitative agreement is obtained tip-molecule distance as only ``fitting parameter.'' Several other thiol-coupled that we have studied also show...
A relatively simple and straightforward procedure for characterizing molecular wires is to measure the conductance spectrum by forming a self-assembled ordered monolayer (SAM) on metallic surface using high scanning-tunneling microscope resolution (STM) tip as other contact. We find that (dI/dV vs. V) can be understood fairly well in terms of model, provided spatial profile electrostatic potential under bias properly accounted for. The effect particularly striking convert symmetric conductor...
We propose an electronic spin-filter device that uses a nonmagnetic triple barrier resonant tunneling diode (TB-RTD). This combines the spin-split levels induced by Rashba spin-orbit interaction and spin blockade phenomena between two regions separated middle in TB-RTD. Detailed calculations using InAlAs/InGaAs material system reveal splitting of peak should be observed I-V curve this as result spin-filtering effect. The filtering efficiency exceeds 99.9% at positions curve.
We present first-principles based calculation of charge transfer and “band lineup” in molecular electronic devices using as an example the device formed by a phenyldithiolate molecule bridging two gold electrodes local-spin-density-functional theory with Gaussian-type orbital basis. show that significant from metal to occurs, reflecting partially ionic character sulfur–gold bond localized interfacial region. Such increases electrostatic potential which changes energy level structures. The...
In this article, we present a computationally efficient, two-dimensional quantum mechanical simulation scheme for modeling electron transport in thin body, fully depleted, n-channel, silicon-on-insulator transistors the ballistic limit. The proposed scheme, which solves nonequilibrium Green’s function equations self-consistently with Poisson’s equation, is based on an expansion of active device Hamiltonian decoupled mode space. Simulation results from method are benchmarked against solutions...
In this paper, we present a method for computing the resistance of molecular wires and illustrate it with systematic theoretical study particular class organic molecules. These molecules consist one or more benzene rings thiol(-SH) group at ends. This end can attach readily to metallic surfaces, thus allowing molecule function as nanoelectronic interconnect. The conduction through these low bias occurs by tunneling, leading resistances that are typically several tens megaohms. goes up...
We introduce the concept of a probabilistic or p-bit, intermediate between standard bits digital electronics and emerging q-bits quantum computing. show that low barrier magnets LBM's provide natural physical representation for p-bits can be built either from perpendicular (PMA) designed to close in-plane transition circular (IMA). Magnetic tunnel junctions (MTJ) using as free layers combined with NMOS transistors three-terminal building blocks large scale circuits perform useful functions....
The transistor celebrated its 75 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sup> birthday in 2022. continued scaling of the defined by Moore's Law continues, albeit at a slower pace. Meanwhile, computing demands and energy consumption required modern artificial intelligence (AI) algorithms have skyrocketed. As an alternative to transistors for general-purpose computing, integration with unconventional technologies has emerged as...
Abstract In the ‘Beyond Moore’s Law’ era, with increasing edge intelligence, domain-specific computing embracing unconventional approaches will become increasingly prevalent. At same time, adopting a variety of nanotechnologies offer benefits in energy cost, computational speed, reduced footprint, cyber resilience, and processing power. The time is ripe for roadmap to guide future research, this collection aims fill that need. authors provide comprehensive neuromorphic using electron spins,...
We provide a theoretical estimate of the thermoelectric current and voltage over Phenyldithiol molecule. also show that is (1) easy to analyze, (2) insensitive detailed coupling contacts, (3) large enough be measured, (4) give valuable information, which not readily accessible through other experiments, on location Fermi energy relative molecular levels. The Fermi-energy poorly understood controversial even though it central factor in determining nature conduction $(n$ or p type). note...
We describe a rigorous and yet computationally simple way of calculating conductance properties molecular conductors, using self-energy matrices to partition the overall structure into device contacts. The standard methods quantum chemistry are combined self-consistently with nonequilibrium Green's function formalism transport in an open system under bias. employ our method demonstrate transition between two limiting cases conduction: metallic conduction gold nanowire resonant phenyl dithiol...
We performed a comprehensive scaling study of Schottky barrier carbon nanotube transistors using self-consistent, atomistic scale simulations. restrict our attention to FETs whose metal source/drain is attached an intrinsic channel. Ambipolar conduction found be important factor that must carefully considered in device design, especially when the gate oxide thin. The channel length limit imposed by source-drain tunneling between 5nm and 10nm, depending on off-current specification. Using...
A program to numerically simulate quantum transport in double gate metal oxide semiconductor field effect transistors (MOSFETs) is described. The uses a Green's function approach and simple treatment of scattering based on the idea so-called Buttiker probes. device geometry permits an efficient mode space that dramatically lowers computational burden use as design tool. Also implemented for comparison are ballistic solution Boltzmann equation drift-diffusion approaches. described some...