Investigation of stochastic resonance in GaAs-based nanowire field-effect transistors (FETs) controlled by Schottky wrap gate and their networks is described. When a weak pulse train is given to the gate of the FET operating in a subthreshold region, the correlation between the input-pulse and source-drain current increases by adding input noise. Enhancement of the correlation is observed in a summing network of the FETs. Measured correlation coefficient of the present system can be larger than that in a linear system in the wide range of noise. An analytical model based on the electron motion over a gate-induced potential barrier quantitatively explains the experimental behaviors.

Abstract-A novel hexagonal binary-decision-diagram (BDD) quantum logic circuit approach for III-V quantum large scale integrated circuits is proposed and its basic feasibility is demonstrated. In this approach, a III-V hexagonal nanowire network is controlled by Schottky wrap gates (WPGs) to implement BDD logic architecture by path switching. A novel single electron BDD OR logic circuit is successfully fabricated on a GaAs nanowire hexagon and correct circuit operation has been confirmed from 1.5 K to 120 K, showing that the WPG BDD circuit can operate over a wide temperature range by trading off between the power-delay product and the operation temperature.Index Terms-Binary decision diagram (BDD), GaAs, logic circuit, Schottky wrap gate (WPG), single electron.

Lateral surface leakage current ͑I s ͒ on an AlGaN / GaN heterostructure was systematically investigated by using a two-parallel gate structure with a gap distance ͑L GG ͒ of 200 nm-5 m. The surface current I s systematically increased as L GG decreased. A simple resistive layer conduction that should show 1 / L GG dependence failed to account for the drastic increase in I s when L GG was reduced to less than 1 m. However, no dependence on L GG was seen in vertical current that flows in the Schottky interface. The I s showed a clear temperature dependence proportional to exp͑−T −1/3 ͒, indicating two-dimensional variable-range hopping through high-density surface electronic states in AlGaN. A pronounced reduction in surface current of almost four orders of magnitude was observed in a sample with SiN x passivation.

In this paper, a vertical-aligned silicon nanowires (Si NWs) array has been synthesized and implemented to the Si NW-array-textured solar cells for photovoltaic application. The optical properties of a Si NWs array on both the plane and pyramid-array-textured substrates were examined in terms of optical reflection property. Less than 2% reflection ratio at 800 nm wavelength was achieved. Using leftover monocrystalline Si (c-Si) wafer (125×125 mm2), a 16.5% energy conversion efficiency, with 35.4% enhancement compared to the pyramid-array-textured c-Si solar cells, was made by the Si NW-array-textured solar cells due to their enhanced optical absorption characteristics. However, without SiNx passivation, the short circuit current reduced due to the increased surface recombination when using Si NWs array as surface texturing, indicating that an optimum surface passivation was prerequisite in high-efficiency Si NW-array-textured solar cells.