Development of Paper Actuators Based on Carbon-Nanotube-Composite Paper.

We propose a unique soft actuator-a paper actuator-based on carbon-nanotube-composite paper (CNT-composite paper), which is a composite of carbon nanotubes (CNTs) and paper. CNT-composite paper has highly efficient properties because of the contained CNTs, such as high electrical conductivity and semiconducting properties. We are considering using CNT-composite paper for various devices. In this study, we successfully developed a paper actuator. We determined the structure of the paper actuator by referencing that of bucky-gel actuators. The actuator operates using the force generated by the movement of ions. In addition to making the paper actuator, we also attempted to improve its performance, using pressure as an index and an electronic scale to measure the pressure. We investigated the optimal dispersant for use in paper actuators, expecting the residual dispersant on the CNT-composite paper to affect the performance differently depending on the type of dispersant. Referring to research on bucky-gel actuators, we also found that the addition of carbon powder to the electrode layers is effective in improving the pressure for paper actuators. We believe that the paper actuator could be used in various situations due to its ease of processing.

Simple annealing process for producing unique one-dimensional fullerene crystal named fullerene finned-micropillar.

We propose a process for easily fabricating a unique one-dimensional fullerene crystal, i.e., a fullerene finned-micropillar (FFMP). To fabricate a one-dimensional fullerene crystal more easily than when using current processes, fullerene was first annealed at 1173 K for 1 h with an argon gas flow of 0.5 L/min. We then examined how the FFMP structure changed when the fabrication process conditions, such as temperature, annealing time, and argon gas flow rate, were varied. FFMPs can be prepared within a short time and may have the same electrical characteristics as other one-dimensional crystals, e.g., fullerene nanowhiskers, so they are expected to be very useful for field-effect transistors, organic photovoltaics, and so on in the near future.

A majority-logic nanodevice using a balanced pair of single-electron boxes.

This paper describes a majority-logic gate device that will be useful in developing single-electron integrated circuits. The gate device consists of two identical single-electron boxes combined to form a balanced pair. It accepts three inputs and produces a majority-logic output by using imbalances caused by the input signals; it produces a 1 output if two or three inputs are 1, and a 0 output if two or three inputs are 0. We combine these gate devices into two subsystems, a shift register and an adder, and demonstrate their operation by computer simulation. We also propose a method of fabricating the unit element of the gate device, a minute dot with four coupling arms. We demonstrate by experiments that it is possible to arrange these unit elements on a GaAs substrate, in a self-organizing manner, by means of a process technology that is based on selective-area metalorganic vapor-phase epitaxy.