Characteristics of intense THz radiation from coherent LO phonons in GaAs/AlAs multiple quantum wells

We have succeeded in generating the intense terahertz (THz) radiation from coherent GaAs-like longitudinal optical (LO) phonons in GaAs/AlAs multiple quantum wells (MQWs). Its radiation power is much larger than that from coherent LO phonons in a GaAs epitaxial film. We report the characteristics of the intense THz radiation from the coherent GaAs-like LO phonons in the MQWs.