Query: Two-dimensional spintronics for low-power electronics

Candidate papers:

abstract: The scaling of complementary metal oxide semiconductor (CMOS) technology is increasingly challenging, but demand for low power data storage and processing continues to grow. The ability to generate, transport and manipulate spin signals in two dimensional (2D) materials suggests that they could provide a suitable platform to build beyond CMOS spintronic devices. Here we review the development of 2D spintronics and explore its potential to deliver devices and circuits for low power electronic applications. We examine the elementary spintronic functionalities and how they can be used to build electronic devices and circuits. We also consider the challenges that must be addressed to deliver practical memory and logic devices.This Review Article examines the development of two dimensional spintronics for low power electronics, exploring potential devices and circuits, as well the challenges that exist in delivering practical applications.
author_names: Xiaoyang Lin

Wei Yang

Kang L Wang

Weisheng Zhao
title: Two dimensional spintronics for low power electronics
venue: Nature Electronics
year: 2019

abstract: The successful isolation of graphene in 2004 has attracted great interest to search for potential applications of this unique material and other newborn members of the two dimensional (2D) family in electronics, optoelectronics, spintronics and other fields. Compared to graphene, the 2D transition metal dichalcogenides (TMDs) have the advantage of being semiconductors, which would allow their use for logic devices. In the past ten years, significant developments have been made in this area, where opportunities and challenges co exist.This thesis presents the results of quantum transport simulations of novel 2D material based tunnel field effect transistors for ultra low power digital applications. Due to their size, such devices are intrinsically dominated by quantum effects. This requires the adoption of a fairly general theory of transport, such as the nonequilibrium Green's functions (NEGF) formalism, which is a method extensively used for the simulation of electron transport in nanostructures.In the first part of this thesis, a brief introduction about the 2D materials, their synthesis and applications is presented. Then, the NEGF formalism is concisely reviewed. This approach is applied to the simulation of two different models of vertical tunnel field effect transistors based on 2D TMD van der Waal heterojunctions (MoS2 and WTe2) To properly describe the system, a coupled effective mass Hamiltonian has been implemented and carefully calibrated to experimental measurements and density functional theory to reproduce the band structure in the energy range of interest for the simulations.This thesis not only demonstrates the ultra steep subthreshold slope potentially expected for these devices, but also provides a physical insight into the impact of the transistor geometry on its performances. In the last and more exploratory part of the manuscript, the effect of rotational misalignment within the two layers of the heterostructure is investigated. Experimentally, such a disorder is difficult to avoid, and it can substantially affect the device performances.Through accurate quantum simulations and deep physical analysis, this study sheds light on the design challenges to be addressed for the development of efficient tunnel field effect transistors based on 2D materials.
author_names: Jiang Cao
title: Tunnel Field Effect Transistors Based on Two Dimensional Materials
year: 2017

abstract: Abstract A multi terminal hybrid system named memtransistor has recently been proposed by combining the concepts of both memristor and field effect transistor (FET) with two dimensional (2D) layered materials as the active semiconductor layer. In the memtransistors, the gate voltages are capable of modulating not only the transport properties of the fabricated FET, but also the resistive switching (RS) behaviors of the memristor. Herein, we employ mechanically exfoliated 2D layered GaSe nanosheets to prepare GaSe based three terminal memtransistors. By using Ag as the electrodes, the memristor exhibits non volatile bipolar RS characteristics. More importantly, under exposure to air for one week, the RS behaviors are dramatically enhanced with the ON/OFF ratio reaching up to 5.3 x 105 and ultralow threshold electric field of ~3.3 x 102 V cm 1. The ultralow threshold electric field of GaSe based memristor could be related to the low migration energy of the intrinsic Ga vacancy in p type GaSe. Moreover, the GaSe based memristor shows long term retention ~104 s) and high cycling endurance ~5000 cycles) simultaneously. Hence, the fabricated three terminal 2D GaSe memtransistors possess high performance with large switching ratios, ultralow threshold electric field, good endurance and long term retention. Furthermore, the device demonstrates gate tunability in RS characteristics, suggesting the promising applications in multi terminal electronic devices with low power consumption and complex functionalities, ranging from non volatile memory, logic device to neuromorphic computing.
author_names: Yang Yang

Huiying Du

Qiang Xue

Xian-hua Wei

Zhibin Yang

Chenggang Xu

Dunmin Lin

Wenjing Jie

Jianhua Hao
title: Three terminal memtransistors based on two dimensional layered gallium selenide nanosheets for potential low power electronics applications
venue: Nano Energy
year: 2019

abstract: Magnetic orderings, i.e. the spontaneous alignment of electron spins below a critical temperature, have been playing key roles in modern science and technologies for both the wide applications of magnetic recording for information storage and the vibrant potential of solid state electronic spin devices (also known as spintronics) for logic operations. In the past decades, thanks to the development of thin film technologies, magnetic thin films via sputtering or epitaxial growth have made the spintronic devices possible at the industrial scale. Yet thinner materials at lower costs with more versatile functionalities are highly desirable for advancing future spintronics. Recently, van der Waals magnetic materials, a family of magnets that can in principle be exfoliated down to the monolayer limit, seem to have brought tremendous opportunities: new generation van der Waals spintronic devices can be seamlessly assembled with possible applications such as optoelectronics, flexible electronics, and etc. Moreover, those exfoliated spintronic devices can potentially be compatible with the famed metal oxide field effect transistor architectures, allowing the harness of spin performances through the knob of an electrostatic field.
author_names: Xiaoxi Li

Baojuan Dong

Xing Sun

Hanwen Wang

Teng Yang

Guoqiang Yu

Zheng Vitto Han
title: Perspectives on exfoliated two dimensional spintronics
venue: Journal of Semiconductors
year: 2019

abstract: Two dimensional materials can be exploited to make a new kind of electronic device that researchers have dubbed an atomristor. In early stage studies, the researchers have demonstrated a possible application for atomristors in low power communications circuits (Nano Lett. 2017, DOI: 10.1021/acs.nanolett.7b04342) The device's name comes from "atomically thin memristor." Memristors are the odd cousin of the electronics family, capable of acting in ways similar to memory cells and transistors. They're particularly promising for use in computer memory because they are nonvolatile: Even when the power is turned off, they hold onto their data. Scientists are also exploring memristors for brainlike computing applications because the devices can both process and store information, like neurons do. And like real neurons, they can exist in a variety of states, not just as a 1 or a 0, because their electrical resistance can be varied along a continuum. Researchers believed that memristors could not
author_names: Katherine Bourzac
title: Two dimensional materials could enable low power telecommunications
year: 2018

abstract: To develop low power, high speed and area efficient design for portable electronics devices and signal processing applications is a very challenging task. Multiplier has an important role in digita.
author_names: Pankaj Kumar

Rajender Kumar Sharma
title: Low Power and Area Efficient Parallel Multiplier Design Using Two Dimensional Bypassing
venue: J. Circuits Syst. Comput.
year: 2017

abstract: There has been an exponential growth in the microelectronics industry over the last 70 years with a consistent miniaturization of transistors' size and increase in the speed and on chip transistors density with reasonable power consumption, as seen in Figure 1 [1] This trend will saturate soon especially due to the unintended thermal noise that is dissipated, as the density of transistors on the chips increase and as the corresponding electronics approach their physical limits. There is a need to implement new processing and computing techniques [2] with more compact size, lower power consumption and enhanced performance. Neuromorphic computing mimics the parallel processing of the mammalian brain and the quantum decoherence within the neurons, and seems to be promising for future applications and needs high speed electronics [3] Quantum computing could enhance the functionalities, storage capabilities, and data manipulation and transmission, for the next generation of devices. Spintronics is an enabling technology to meet the speed, power, and scalability requirements for quantum information and neuromorphic computing [4 5] The non volatile nature of spintronic memory could help to tackle power efficiency challenges of microelectronics. Spin of a material is directly related with magnetic, electrical, and optical properties. It is necessary to investigate materials and understand their properties to control and manipulate their spin and use for spintronic applications. However, most materials show conducive properties for spintronics at cryogenic temperatures, which limits their practical applications. There is a need to investigate spintronic materials for quantum applications at room temperature (RT)
author_names: Vishal Saravade

Amirhossein Ghods

Andrew Woode

Chuanle Zhou

Ian T Ferguson
title: GaN based Room Temperature Spintronics for Next Generation Low Power Consumption Electronic Devices
venue: 2019 IEEE 16th International Conference on Smart Cities: Improving Quality of Life Using ICT IoT and AI (HONET ICT)
year: 2019

abstract: Abstract Synapses in biology provide a variety of functions for the neural system. Artificial synaptic electronics that mimic the biological neuron functions are basic building blocks and developing novel artificial synapses is essential for neuromorphic computation. Inspired by the unique features of biological synapses that the basic connection components of the nervous system and the parallelism, low power consumption, fault tolerance, self learning and robustness of biological neural systems, artificial synaptic electronics and neuromorphic systems have the potential to overcome the traditional von Neumann bottleneck and create a new paradigm for dealing with complex problems such as pattern recognition, image classification, decision making and associative learning. Nowadays, two dimensional (2D) materials have drawn great attention in simulating synaptic dynamic plasticity and neuromorphic computing with their unique properties. Here we describe the basic concepts of bio synaptic plasticity and learning, the 2D materials library and its preparation. We review recent advances in synaptic electronics and artificial neuromorphic systems based on 2D materials and provide our perspective in utilizing 2D materials to implement synaptic electronics and neuromorphic systems in hardware.
author_names: Shuiyuan Wang

David-Wei Zhang

Peng Zhou
title: Two dimensional materials for synaptic electronics and neuromorphic systems
venue: Science Bulletin
year: 2019

abstract: Schrodingerand Poisson equations are solved self consistently in order to obtain the potential and charge density distribution in n type GaN nanowalls tapered along c axis by different angles. The
author_names: Swarup Deb

Subhabrata Dhar
title: Wedge Shaped GaN Nanowalls: A Potential Candidate for Two Dimensional Electronics and Spintronics
year: 2018

abstract: Gas sensors based on metal oxide semiconductor transistor with the polysilicon gate replaced by a gas sensitive thin film have been around for over 50 years. These are not suitable for the emerging mobile and wearable sensor platforms due to operating voltages and powers far exceeding the supply capability of batteries. Here we present a novel approach to decouple the chemically sensitive region from the conducting channel for reducing the drive voltage and increasing reliability. This chemically gated field effect transistor uses silicon nanowire for the current conduction channel with a tin oxide film on top of the nanowire serving as the gas sensitive medium. The potential change induced by the molecular adsorption and desorption allows the electrically floating tin oxide film to gate the silicon channel. As the device is designed to be normally off, the power is consumed only during the gas sensing event. This feature is attractive for the battery operated sensor and wearable electronics. In addition, the decoupling of the chemical reaction and the current conduction regions allows the gas sensitive material to be free from electrical stress, thus increasing reliability. The device shows excellent gas sensitivity to the tested analytes relative to conventional metal oxide transistors and resistive sensors.
author_names: Jin-Woo Han

Taiuk Rim

Chang-Ki Baek

Meyya Meyyappan
title: Chemical Gated Field Effect Transistor by Hybrid Integration of One Dimensional Silicon Nanowire and Two Dimensional Tin Oxide Thin Film for Low Power Gas Sensor.
venue: ACS applied materials interfaces
year: 2015