Wrinkled Sige Nanofilms As A Source Of Terahertz Radiation

We demonstrate that the wrinkled Si1-xGex/Si1-y Ge-y films can serve as radiation sources, which emit electromagnetic waves in a very wide range of the frequencies including the terahertz band from 0.3 to 3 THz. The emission mechanism is based on the change of acceleration of carriers, when they travel along the sinusoidal trajectory in wrinkled Si1-xGex/Si1-yGey films, a manner similar to synchrotron radiation with undulators, or like a free-electron laser.