Terahertz Frequency Comb (IMAGE) California Institute of Technology Caption Extremely short pulses of red light (quadrillionths of a second) are generated by a titanium-sapphire laser, and then converted into terahertz light. The red glowing component in the photograph shown above is the titanium-sapphire crystal, surrounded by mirrors used in the laser. Credit Brandon Carroll/Caltech Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.