Energy scalable and high beam quality THz-wave parametric oscillator using surface emitted cavity configuration

We describe a possibility of the output THz-wave scaling in surface emitted TPO by simply using a larger beam size along with higher pump energy. The output energy was as six times as higher than that of the conventional surface emitted TPO though the input energy and pump beam cross-section area each increased 2.9 times. The efficiency enhancement by increasing a pump beam size was also obtained. The beam quality factors (M²) of THz-wave were also measured to be 1.15 x 1.25.