A powerful amplifier for boosting Terahertz waves ― radiation that lies between the microwave and infrared regions of the spectrum ― is reported this week online in Nature Photonics. This study could be the key to unlocking the potential of terahertz waves (THz) for applications in pharmaceuticals research, security screening for explosives or drugs, and biological imaging.

Terahertz waves are often very weak, which has so far limited their use. Nathan Jukam and colleagues have shown that a powerful amplifier for boosting THz waves can be made by integrating a special switch with a semiconductor laser. This can override the usual limit of the signal strength in the short time period before the laser settles into normal operation mode. The researchers show that the signal can be amplified by a factor of 400, which could greatly enhance the performance of THz equipment.