Abstract

Nowadays terahertz (THz) time-domain spectroscopy attracts much attention of scientists because of promising applications in fingerprint spectroscopy, environment monitoring, semiconductor and medical imaging and law enforcement. Unlike other methods the THz spectroscopy allows to measure directly the strength of the field and to get in-situ the data of the real and imaginary components of refractive index. Although many principal technical advances had been witnessed in developing intense THz sources, including, for example, quantum cascade THz laser and so on, there is still a strong need to develop more powerful and tunable THz-radiation sources. In our opinion beta- barium borate (β-BaB₂O₄) crystals (BBO) have high impact in harmonic frequency generation and even parametric amplifiers for this spectral range. The BBO crystals are transparent in submillimeter-wave range and more importantly have large birefringence and strong dispersion in this field.

© 2011 Optical Society of America