Quantized conductance atomic switch

Abstract

A large variety of nanometre-scale devices have been investigated in recent years that could overcome the physical and economic limitations of current semiconductor devices. To be of technological interest, the energy consumption and fabrication cost of these 'nanodevices' need to be low. Here we report a new type of nanodevice, a quantized conductance atomic switch (QCAS), which satisfies these requirements. The QCAS works by controlling the formation and annihilation of an atomic bridge at the crossing point between two electrodes. The wires are spaced approximately 1 nm apart, and one of the two is a solid electrolyte wire from which the atomic bridges are formed. We demonstrate that such a QCAS can switch between 'on' and 'off' states at room temperature and in air at a frequency of 1 MHz and at a small operating voltage (600 mV). Basic logic circuits are also easily fabricated by crossing solid electrolyte wires with metal electrodes.

Electrochemical dynamics of nanoscale metallic inclusions in dielectrics

“…However, manual manipulation using scanning tunneling microscopy is slow and inefficient, and not device-friendly compared with methods such as using local electric fields. Indeed, devices based on the field-driven migration of metal inclusions (such as resistive switching or memristive devices) [7][8][9] have attracted broad interest recently and have shown great potential as a disruptive technology for a number of applications including nonvolatile memory [10][11][12][13] , logic [14][15][16] and neuromorphic computing 17 . In these devices, the resistive switching is normally attributed to filament formation caused by the movement of metal inclusions in the insulating dielectric film 9,10,[18][19][20] .…”

“…In these devices, the resistive switching is normally attributed to filament formation caused by the movement of metal inclusions in the insulating dielectric film 9,10,[18][19][20] . Attempts to microscopically study the filament growth processes have been carried out using scanning probe microscopy 15,21 and highresolution transmission electron microscopy 19,20,[22][23][24] techniques. For example, a recent experiment reveals different filament growth modes 20 and shows that filament formation can be achieved in the form of metal nanoclusters.…”

A Family of Electronically Reconfigurable Nanodevices

“…[4] The switching mechanism involved changes to the Schottky-like barrier at a Pt/TiO 2 interface caused by the drift of positively charged oxygen vacancies (V O s) under an applied electric field. These nanoscale switches may enable a new type of nonvolatile random access memory (RAM) [15][16][17][18][19][20] and analog switching for neuromorphic computing. [21] Here, we show that the previously reported nanoswitches are actually just one member in a family of memristively switched reconfigurable devices that behave as a network of parallel and series memristors and rectifiers.…”

Nanoscale Electronic Inhomogeneity in In2Se3 Nanoribbons Revealed by Microwave Impedance Microscopy

“…Probing these non-uniform phases provides not only much knowledge of the underlying interactions, but also valuable information for applications of the domain structures. In particular, spatially resolved properties are of significant interest for phase change and other switching materials to be on board the nanoelectric era [5][6][7][8][9] .While a number of contrast mechanisms 15 have been employed to visualize the electronic inhomogeneity, established scanning probe techniques do not directly access the low-frequency (f) complex permittivity ε(ω) = ε′ + iσ/ω, where ε′ is the dielectric constant and σ the conductivity, which holds a special position to study the ground state properties of materials. For local electrodynamic response, near-field technique is imperative to resolve spatial variations at length scales well below the radiation wavelength 16 .…”