Terahertz sources based on stimulated polariton scattering

In this paper we review the field of terahertz (THz) sources which make use of the nonlinear, stimulated polariton scattering (SPS) process. A historical perspective of the technology is offered, in addition to an investigation of modern SPS-based THz sources. Breakthroughs in these source technologies have coincided with rapid developments in laser technology over the past 10 years. We are now in an age where pulsed SPS-THz sources are generating peak powers in excess of 50 ​kW, and continuous wave SPS-THz sources can be produced using diode pump powers as low as 2.3 ​W. The versatility of this approach to THz generation has enabled the generation of coherent THz radiation across continuous wave (CW), nanosecond-, and picosecond-pulsed modalities, with sources spanning the frequency range 0.5–13 ​THz. Being based on robust and well-developed, crystalline solid-state laser technology, these sources hold great promise as an enabling technology for a plethora of THz applications.