We performed Monte Carlo simulation of electron response to a strong pumping wave (443 GHz) and weak signal harmonic waves (886 and 1329 GHz) in silicon. A negative dynamic conductivity is found to arise for 1329 GHz above a threshold value of the pumping wave amplitude and below a maximum value of the signal wave amplitude in a limited range of phase difference between the waves.
Jean-François Molinari, Antonio Joaquin Garcia Suarez, Ghatu Subhash
Romain Christophe Rémy Fleury, Janez Rus