Methods

Tilted pulse front THz generation

The "THz gap" of the electromagnetic spectrum, ranging between 10¹¹-10¹³ Hz has been "filled" owing to recent advents in THz generation techniques. With the non-collinear tilted pulse front optical rectification technique^*, single cycle fields with the spectral range of 0.1~3 THz and with peak field strengths >100kV/cm have become tabletop available, and provides access to various nonlinear applications of THz spectroscopy and coherent control of electrons in semiconductors, collective crystal motions, molecular rotations and various others. A typical single cycle THz pulse measured by optical electro-optic sampling is shown.

*Hebling, J., Yeh, K.-L., Hoffmann, M. C., Bartal, B. & Nelson, K. A. Generation of high-power terahertz pulses by tilted-pulse-front excitation and their application possibilities. J. Opt. Soc. Am. B 25, 6–19 (2008).