Fig. 3
Electrical characteristics of the SWNT/POM network. a I–V characteristics of sample A (rinsed with ethanol) lying between electrodes (1) and (2) in Fig. 2b. b Plot of the measured current versus time of sample A when VB was set at 150 V. (Inset) Magnification of periodic current impulses. c I–V curve of the water-treated POM/SWNT samples (sample B). A number of NDR peaks are noticeable over approximately 80 V. d Time dependence of the current at 80 V. (Inset) Magnification of periodic base current modulation. e Poincaré plots formed by changing the applied voltage obtained using sample A. (inset) Example of impulse trains and sequences of the ISIs (\(\cdots ,t_n,t_{n + 1}, \cdots\)). f Dependence of ISIs for sample A on the concentration ratio of POM to SWNT
