High-order sideband generation in bulk GaAs

When an intense THz field at frequency fTHz is applied to excitons resonantly created in bulk GaAs by a near infrared laser at frequency fNIR, sidebands are observed at frequencies fsideband = fNIR + 2nfTHz, where n is an integer. At temperature T = 10 K, sidebands of order −4 ≤ 2n ≤ 16 are observed. Sidebands up to 10th order persist at 170 K.