 When the electrons jump, they emit photons of light.The quantum cascade laser was co-invented by Alfred Y. Cho, Claire F. Gmachl, Federico Capasso, Deborah Sivco, Albert Hutchinson, and Alessandro Tredicucci at Bell Laboratories in 1994.On April 4, 1994, the Bell Labs team filed U.S. patent #5,457,709 that was issued on October 10, 1995.