RIKEN advanced tera-photonics research
Terahertz (THz)-wave research is now entering a new phase as a technology supporting the next generation of wireless communications (Beyond5G/6G). Semiconductor and photonics technologies have evolved in a way that opens up the terahertz wave region as the boundary between radio-wave and light. And new devices have begun to be developed that integrate heterogeneously.
Lithium niobate nonlinear crystals still play an important role in the above field, however, they have spent a long time as practical material soon after the invention of the laser. But just as semiconductor silicon is an important material that underpins today's devices, lithium niobate is the nonlinear optical crystal that has found further importance with the development of frequency.
Attracted by versatile potential of the crystal, we have been studying the generation of THz waves using lithium niobate crystals by means of quantum optical wavelength conversion from the intense lasers. And we are recently trying to make a high-brightness THz-wave source in a palmtop-size THz-wave source. It has been brought by discovering efficient conversion between THz-wave and near-infrared light by suppressing stimulated Brillouin scattering and by discovering backward THz-wave parametric oscillation.
In this talk, I will present the results of cutting-edge research, unraveling the results of research I have been engaged in at RIKEN for more than 20 years.