Point source terahertz optics

Abstract

We demonstrate an ultrafast 10 μm sized, electric dipole source of terahertz radiation closely coupled to a 1 cm spherical mirror. This optical approach has the advantages of subpicosecond response times with essentially complete collection efficiency. Using this technique, we have generated and detected subpicosecond freely propagating electrical pulses.

CW THz Wave Generation System with Diode Laser Pumping

“…Our group succeeded in generating wide frequencytunable high power THz wave signals from GaP with Q-switched pulse pumping [6]. Also, time domain THz sources have been developed based on femto-second pulsed lasers [7][8][9][10]. Compared to pulsed THz sources, continuous-wave (CW) THz sources provide a THz spectrum with a narrower line width and a higher spectral THz power [11,12].…”

THz-TDS using a photoconductive free-space linear tapered slot antenna transmitter

“…This method functions well but has several issues: the resulting antenna is delicate, manufacturing requires harsh etchants, and the conductor loss is relatively high. The issues associated with guided-wave antennas are mostly overcome by optical lensing [7,8] which therefore became the dominate method for guiding the electromagnetic field generated by a photoconductive switch. The main issues associated with substrate lenses are: pulse attenuation and dispersion, lens manufacturing, alignment, physical size, and cost.…”

“…Subsequently, extensive research was pursued in freespace antenna design and optimization. At this point two approaches appeared for collimating the generated THz field: guided-wave electronic antennas [2][3][4][5][6] and optical lensing from a point source [7,8].…”

The Effect of Laser Beam Intensity on Self-Focusing and Terahertz Radiation at Low Frequency Range (0.1 and 0.5) THZ

“…Terahertz (THz) technology is relatively new, and has only seen significant progress in the last three decades [1,2]. Nevertheless, the wide range of possible applications of today's THz technology stimulate intense attention of specialists in various fields, such as imaging, sensing, quality control, wireless communication, and basic science [3][4][5][6][7][8][9].…”