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On an Au(111) surface, Au atomic diffusion induced by a voltage pulse was demonstrated using a scanning tunneling microscope (STM) with an Au tip in air. Applying a voltage pulse as a trigger, we observed local diffusion of Au atoms around the position where the voltage pulse was applied. Upon repeating tip scanning, fingerlike stripes grew gradually from a step; the direction of the stripes was affected by the structure of the Au(111) surface and the tip-scan direction. In our experiments, movable Au atoms on the local area were swept by tip scanning via the field gradient effect. Local atomic Au diffusion could be induced since activation energy was reduced by applying the voltage pulse.

A nano-scale bonding process using a multi-wall carbon nanotube (CNT) has been successfully applied in a scanning electron microscope (SEM)/scanning tunneling microscope (STM) combined system. Under the SEM observation, a Ti-coated STM tip was approached onto a CNT bridging Ti pads, which is patterned with a 4 µm gap on a SiO2 surface, to investigate the conduction property of the CNT. A voltage pulse of 12 V peak and 50 µs duration was applied in order to deposit Ti clusters onto the CNT, which is well known as a field evaporation process in the STM regime. The two-terminal current-voltage characteristics of the CNT have been improved from a nonlinear behavior at 2.5 V of 208 kΩ to a linear one of 1.8 kΩ.

The time resolved bipolar resistance switching in a Pt/Cr-doped SrZrO3/SrRuO3 device has been investigated using pulse voltage. The required switching time between the high and low resistance states (HRS and LRS) is studied as a function of the pulse height and width. The resistance switching is found to be less dependent on the pulse height in the short pulse region. For LRS→HRS and HRS→LRS switching minimum switching times of ∼500 and ∼100 ns are required respectively, at a pulse height above the dc switching voltage. The authors attribute the distinction in the switching time to different switching mechanisms.

The characteristics of a multichannel arc gap are investigated experimentally in the voltage range of less than 45 kV using a ferrite sharpener. The gap comprises 12 or 24 steel needle electrodes and a brass rod electrode. We examined the characteristics of the number of arc channels when the following parameters were changed independently: (1) rise rate of voltage pulse applied to the gap, (2) length of feeders which transmit voltage pulse from the ferrite sharpener to each needle electrode, (3) gap length, (4) kind and pressure of intergap gas and (5) with and without UV irradiation.

A reflective bistable twisted nematic (BTN) liquid crystal display has been developed. It combines the advantages of a truly reflective display without the rear polarizer, and the bistable nature of the zero voltage state. It was found experimentally that switching between the two bistable twist states could be achieved by adjusting the magnitude of the selection voltage pulse, just like the case in transmittive BTNs. In demonstrating the reflective BTN, we also show for the first time bistability between the -36° and 324° twist states.

An air-core step-up transformer with a high coupling factor has been developed to generate a high voltage pulse for charging the pulse forming line of a relativistic electron beam source.A beam source using the transformer was constructed. It operated well for the beam injection into a toroidal system.

Charge density waves pinned by disorder have many possible metastable configurations. The existence of metastable states give rise to generic glasslike behavior including hysteresis and power law time decays of the polarization. The characteristic behavior is controlled by high-energy metastable states which are marginally stable to perturbations. One consequence is a dynamic memory effect, whereby the system can be trained to remember the length of a voltage pulse.

On the application of short voltage pulse to selenium photocells, selenium rectifiers, and cuprous oxide rectifiers in the reverse direction, turnover phenomena are observed. The turnover behaviour of photocells is sensitive to light and the photo-breakdown occurs when the intensity of illumination exceeds a certain value.