Electron emission from thin film optically enhanced nano-forest cathodes

Optically enhanced nano-forest cathodes are electron sources developed for high power devices. The principle of cathode operation is based on coherent light coupling photon energy into resonantly tuned, nano-meter sized antennae, which can theoretically generate large current densities with little applied energy. Pulsed laser energy can be coupled into pins on the order of the wavelength in length, thereby heating the tips of the pins, resulting in thermionic or thermo-field emission. This paper presents measured electron emission data from nano-forest materials and compares them to theoretical estimates of electron emission.