Double-Gate Operation of Metal Nanodot-Array-Based Single-Electron Device

Multidot single-electron devices (SEDs) can realize new types of computing technologies, such as reconfigurable and reservoir computing. The self-assembled metal nanodot-array film attached with multiple gates is a candidate for use in such SEDs to achieve high functionality. However, the single-electron properties of such a film have not yet been investigated in use with optimally controlled multiple gates because of structural complexity having many nanodots. In this study, Fe nanodot-array-based double-gate SEDs were fabricated and their single-electron properties modulated by the top- and bottom-gate voltages (VT and VB, respectively) were investigated. As reported in our previous study, the drain current (ID) exhibited clear oscillations against VB (i.e., Coulomb blockade oscillation) in a part of the devices, originating from a single dot among several dots. The phase of the Coulomb blockade oscillation systematically shifted with VT, indicating that the charge state of the single dot was clearly controlled by both the gate voltages despite the multidot structure and the metal multidot SED has potential for logic-gate operation. The top and bottom gates affected the electronic state of the dot unevenly owing to the geometrical effect caused by the dot shape and size of the surrounding dots.

Schemes for Single Electron Transistor Based on Double Quantum Dot Islands Utilizing a Graphene Nanoscroll, Carbon Nanotube and Fullerene

The single electron transistor (SET) is a nanoscale switching device with a simple equivalent circuit. It can work very fast as it is based on the tunneling of single electrons. Its nanostructure contains a quantum dot island whose material impacts on the device operation. Carbon allotropes such as fullerene (C60), carbon nanotubes (CNTs) and graphene nanoscrolls (GNSs) can be utilized as the quantum dot island in SETs. In this study, multiple quantum dot islands such as GNS-CNT and GNS-C60 are utilized in SET devices. The currents of two counterpart devices are modeled and analyzed. The impacts of important parameters such as temperature and applied gate voltage on the current of two SETs are investigated using proposed mathematical models. Moreover, the impacts of CNT length, fullerene diameter, GNS length, and GNS spiral length and number of turns on the SET’s current are explored. Additionally, the Coulomb blockade ranges (CB) of the two SETs are compared. The results reveal that the GNS-CNT SET has a lower Coulomb blockade range and a higher current than the GNS-C60 SET. Their charge stability diagrams indicate that the GNS-CNT SET has smaller Coulomb diamond areas, zero-current regions, and zero-conductance regions than the GNS-C60 SET.

Controlling the Optical and Catalytic Properties of Artificial Metalloenzyme Photocatalysts Using Chemogenetic Engineering

Visible light photocatalysis enables a broad range of organic transformations that proceed via single electron or energy transfer. Metal polypyridyl complexes are among the most commonly employed visible light photocatalysts....

High-Temperature Single-Electron Transistors Based on Molecules and Small Nanoparticles.

The material of the defense of the dissertation for the degree of Doctor of Physical and Mathematical Sciences – the first in Russia doctoral dissertation on molecular singe-electronics is presented. The relevance of the development, creation and research of single-electron transistorswith high charge energy and operating temperature for the creation of fundamentally new nanoelectronic devices applicable in wide practice and ensuring breakthrough research in various fields is noted, the necessity of using quantum dots (molecules/nanoparticles) of atomic-molecular scale for this is shown, the formulation of the research problems is formulated, the physical and technological methods of fabrication and analysis used are listed, the main results of the work are presented and their significance for the development of highly sensitive sensing, quantum informatics and quantum metrology is discussed.

Corrigendum: Identifying single electron charge sensor events using wavelet edge detection (2015 Nanotechnology 26 215201)

The simulated noise used to benchmark wavelet edge detection in this work was described incorrectly. The correct description is given here, and new results based on noise that matches the original description are provided. The results support our original conclusion, which is that wavelet edge detection outperforms thresholding in the presence of white noise and 1/f noise.

High-frequency rectifying characteristics of metallic single-electron transistor with niobium nanodots

Metallic single-electron transistors (SETs) with niobium nanodots were fabricated, and their high-frequency rectifying characteristics were evaluated. By reducing the gap size of the electrodes and film deposition area to nanometer scale, improved SET characteristics with gate control, and better frequency response of the rectifying current with gentler decrease than 1/f at high frequency were achieved. The comparison between the characteristics of micrometer- and nanometer-size devices are made, and the reason for their differences are discussed with a help of simulation based on the experimentally extracted parameters.

Parallel Comparator based voltmeter using Single Electron Tunneling Transistor

By manipulating an electron that tunnels the tunnel junction of a single electron transistor, one will be able to reach a standard output logic “1” or logic “0”. The operation of the Single Electron Transistor (SET) is depending upon the bias voltage as well as the input signal(s). By varying the input voltage levels of a SET, the output voltage levels can significantly be changed on the basis of tunneling of an electron whether tunneling happened or not. As our concentration is the measuring of an unknown voltage, we are to implement a voltmeter system to provide a digital output of 3 bits whenever an unknown input voltage is kept in touching in the input terminal. A reference/standard voltage (say 8mV) will be connected in series with eight resistances ( 8 Rs) for the purpose of making a seven threshold voltages, for 7 comparators, in an ascending order of values from ground to reference voltage for seven comparators which are used in this present work. The voltmeter implemented consists of (i) a voltage divider, (ii) a set of seven comparators, (iii) seven Exclusive-OR gates and (iv) three 4-input OR gates. The concepts of implementing “Parallel Comparator based voltmeter” is discussed in two ways (i) by classical block diagram and (ii) using Single electron transistor based circuit. The measuring of an input analog voltage will not be the same as the digital output value. A 3-bit output indicates that the input analog voltage must lie on within a particular small range of voltage. The encoder circuit which is connected to the outputs of the comparators is hard to construct whenever the three terminals output are expressed with the output variables (Wi) of the comparators. For simple and user-friendly circuit, the outputs (Wi) of the comparators are modified to Di variables so as to get the same 3-bit encoder/voltmeter output. For this purpose, 7 extra component called 2-input XORs based on SET are used. Seven such XORs are set, and the output of them are passed to three 4-input OR gates according to the required logic expressions. It is found that all the output data of the voltmeter are coherently matched with the theoretical aspects. Processing delays are found out for all circuits. Power consumptions of all of them are shown in tabular and graphical forms. All the circuit we are intending to make are provided in due places with their logic circuit or simulation set and the simulation results are provided as well. Different truth tables are given for keeping track of whether input-output relationships matches with the theoretical results. We have thought of whether the present work circuits are faster or slower than the circuits of CMOS based-circuits. The power consumed at the time of tunneling event for a circuit is measured and sensed that it exists in the range between 1×10^(-18) Joules to 22×10^(-18)Joules which is very small amount. All the combinational circuits presented in this work are of SET-based.