Subcycle surface electron emission driven by strong-field terahertz waveforms
Shaoxian Li, Ashutosh Sharma, Zsuzsanna Márton, Priyo S. Nugraha, Csaba Lombosi, Z. Ollmann, István Márton, Péter Dombi, János Hebling, J. A. Fülöp
Abstract
The advent of intense terahertz (THz) sources opened a new era when the demonstration of the acceleration and manipulation of free electrons by THz pulses became within reach. THz-field-driven electron emission was predicted to be confined to a single burst due to the single-cycle waveform. Here we demonstrate the confinement of single-cycle THz-waveform-driven electron emission to one of the two half cycles from a solid surface emitter. Either the leading or the trailing half cycle was active, controlled by reversing the field polarity. THz-driven single-burst surface electron emission sources, which do not rely on field-enhancement structures, will impact the development of THz-powered electron acceleration and manipulation devices, all-THz compact electron sources, THz waveguides and telecommunication, THz-field-based measurement techniques and solid-state devices.