Experimental study of space-charge-limited flows in a nanogap

An experimental investigation of space-charge-limited flow of current in a nanogap is presented. Electrodes with gap size d similar to 70-110 nm corresponding to d/lambda(0) similar to (1-5) x 10(3), where lambda(0) is the de Broglie wavelength of the space-charge electrons are experimented. Unlike classical Child-Langmuir's (CL) law, the current density varies as square root of applied voltage (V-1/2), when d becomes comparable to lambda(0). Additionally, a transition regime has been found for the 90 nm gap size where the CL law appears at voltages >45 V. At d = 110 nm, the system is found to exhibit purely classical behavior. (C) 2008 American Institute of Physics.