Efficient terahertz generation in highly nonlinear organic crystal HMB-TMS

Area of Science:

• Nonlinear Optics
• Terahertz (THz) Science
• Materials Science

Background:

• Terahertz (THz) wave generation is crucial for various applications.
• Organic nonlinear optical crystals offer potential for efficient THz sources.
• Developing compact and high-performance THz sources remains a challenge.

Purpose of the Study:

• To investigate the generation of strong and broadband THz pulses.
• To explore the efficacy of HMB-TMS organic crystals for THz wave generation.
• To optimize THz pulse characteristics through collinear phase-matching.

Main Methods:

• Optical rectification of near-infrared femtosecond pulses.
• Utilizing HMB-TMS (2-(4-hydroxy-3-methoxystyryl)-3-methylbenzo[d]thiazol-3-ium 2,4,6-trimethylbenzenesulfonate) single crystals.
• Collinear phase-matching technique for efficient THz wave generation.

Main Results:

• Generation of single-cycle THz pulses with a peak electric field of 0.66 MV/cm.
• Achieved a broad THz bandwidth from 0.1 to 5.4 THz.
• Obtained a pump-to-THz energy conversion efficiency of 0.23% with 1 µJ THz energy.

Conclusions:

• HMB-TMS crystals are highly effective for generating strong and broadband THz pulses.
• The demonstrated method offers a promising route for compact and efficient THz sources.
• Optimal molecular orientation and large optical nonlinearity in HMB-TMS are key to efficient THz generation.