Enhancement of Coulomb blockade and tunability by multidot coupling in a silicon-on-insulator-based single-electron transistor

Abstract

Articles you may be interested inSingle-electron transistors based on self-assembled silicon-on-insulator quantum dots Appl. Phys. Lett. 96, 142108 (2010); 10.1063/1.3383235 Isolated double quantum dot capacitively coupled to a single quantum dot single-electron transistor in silicon A dual-gate-controlled single-electron transistor with coupled dot geometry has been fabricated on a silicon-on-insulator structure. Coupled dots are defined by tunable gates which are designed to separately control the tunneling potential barriers to compensate for disorder due to size fluctuation in quantum dots. The Coulomb-blockade phenomena observed in linear and nonlinear transport regimes were found to be enhanced by the multidot coupling. The Coulomb staircase ͑nonlinear effect͒ appears more clearly with the increasing number of coupled dots, indicating definite suppression of the inevitable cotunneling process. In the linear regime, the frequency of Coulomb oscillation was able to be tuned by changing the interdot coupling strength. These results indicate that enhancement of the Coulomb blockade and tunability can be achieved through replacing the traditional single dot by gate-controlled multidots in future single-electron devices.

Ambipolar coulomb blockade characteristics in a two-dimensional Si multidot device

“…In applying Si SET devices to new functional devices such as quantum cellular automata (QCA) [8], [9] and photoimaging devices [10], it is necessary to develop the SET/SHT devices composed of a two-dimensional (2-D) array of Si dots. So far, most of the Si-based SET devices utilize single dot or one-dimensional (1-D) dot array [1], [11], [12], while only one paper has been reported [13] on the transport properties in the 2-D Si dots, to our knowledge. In [13], 2-D multidots composed of an undulated ultrathin silicon-on-insulator layer were formed using anisotropic wet etching in an alkaline-based solution.…”

Coherent switching by detuning a side-coupled quantum-dot system

“…1,2 The advances in current progress in microfabrication technology have enabled studies of transport through quantum systems in which the charge carriers behave coherently. In recent years, much effort has been devoted to coherent transport in various coupled quantum-dot-and quantum-wire-associated structures such as open quantum dot, 3-7 embedded dot, [8][9][10] sidecoupled dot, [11][12][13][14][15] antidot, [16][17][18] multidot, 19,20 and coupled quantum-wire systems. [21][22][23] Rich quantum interference phenomena in mesoscopic systems have been discussed in various aspects such as bound-state features, [24][25][26][27][28] spin-related switching, [29][30][31] phase switching, 32,33 and Andreev current switching.…”