THz wave generation using hybrid electro-optic modulators: simulations and experimental results

A novel scheme to generate terahertz waves is proposed and numerically and experimentally investigated. The configuration of the proposed technique consists of cascaded electro-optic modulators to apply sinusoidal hybrid modulation of optical amplitude and phase onto the incident light. The key to drive an efficient terahertz wave relies on the spectral tuning capability of the optical spectrum of the modulated light. The optical power of sidebands around the optical frequency of the seed laser can be significantly reduced by optimizing the relative phase offset of microwave signal applied to the amplitude and phase modulation and the DC bias of amplitude modulator. In this way, a proof-of-concept dual frequency-like laser with a spectral distance of 86.4 GHz has been successfully generated.