Better ablate than never

Terahertz emission from gallium arsenide devices can be boosted by femtosecond laser ablation of the material's surface, according to a study at Okinawa Institute of Science and Technology Graduate University (OIST). Given a sufficiently powerful laser it is possible to engrave the surface with microscopic grooves and ripples that can boost THz emission by up to 65 percent. THz radiation lies between infrared and microwave radiation in the electro-magnetic spectrum and has potential for wireless communications, medical imaging and new advances in spectroscopy.