Improving faint-signal sensitivity of electrolyte-gated carbon nanotube field-effect transistors using external noise

Stochastic resonance (SR) in carbon nanotube field-effect transistors (CNT-FETs) was investigated to enhance their weak-signal response. When weak pulse trains were applied to the gate of a CNT-FET operating in a subthreshold regime, the correlation coefficient between the input and output voltages increased upon addition of noise with optimized intensity. SR was observed both in air and in solutions. These results indicate that external noise is able to improve faint-signal sensitivity of CNT-FETs. Therefore, CNT-FETs based on stochastic resonance are promising candidates for highly sensitive label-free sensors.