Yuzuru Uehara

Broadband and high power terahertz pulse generation beyond excitation bandwidth limitation via χ (2) cascaded processes in LiNbO 3

We proposed a novel THz generation technique beyond the limitation of the input optical pulse width, based on phase modulation via cascaded chi((2)) process. When intense THz electric field generated by optical rectification lies in electro-optic (EO) crystal, emitted THz field gives phase modulation to the optical excitation pulse. The phase modulation causes excitation pulse narrowing and consequently gives rise to the enhancement of conversion efficiency and THz wave bandwidth broadening. We experimentally realize this generation technique with high chi((2)) EO crystal LiNbO(3) and with subpicosecond pulse from Yb-doped fiber laser. It opens new concept of THz technologies.

Broadband and high power monocycle terahertz pulse generation by χ (2) cascaded processes in LiNbO 3

We propose a novel technique for the generation of high power monocycle terahertz pulse beyond the excitation pulse width limitation. Optical pulse may get modulated by emitted intense THz electric field. This causes excitation pulse compression and consequently gives rise to the enhancement of generation efficiency and its bandwidth. We experimentally demonstrate this χ(2) cascaded processes using tilted wavefront excitation beam by LiNbO3 from Ti:Sapphire and Yb doped fiber laser.

Terahertz pulse generation beyond excitation pulse limitation by χ(2) cascaded processes

We propose a novel technique for the generation of high power monocycle terahertz (THz) pulse beyond excitation pulse width limitation. When intense THz electric field generated by optical rectification lies in EO crystal, optical pulse itself gets modulated by emitted THz electric field. It causes excitation pulse compression and consequently gives rise to the enhancement of generation efficiency and its bandwidth. We experimentally demonstrate it using tilted wavefront excitation beam by LiNbO3 from Yb doped fiber laser.