Optical rectification and electro-optic sampling in quartz

Area of Science:

• Solid-state physics
• Nonlinear optics
• Terahertz (THz) science and technology

Background:

• Alpha-quartz (α-quartz) is a widely used crystalline material.
• Its optical and mechanical properties make it suitable for various applications.
• Understanding its nonlinear optical response at THz frequencies is crucial for advanced applications.

Purpose of the Study:

• To investigate the terahertz (THz) optical rectification (OR) and electro-optic sampling (EOS) responses of z-cut α-quartz.
• To assess the suitability of crystalline quartz as a THz electro-optic medium for high electric-field detection.
• To characterize the THz emission properties of quartz as a substrate.

Main Methods:

• Experimental measurement of the electro-optic sampling (EOS) response of z-cut α-quartz.
• Experimental measurement of the terahertz (THz) optical rectification (OR) response of z-cut α-quartz.
• Analysis of the frequency dependence and thickness independence of the THz responses.

Main Results:

• Z-cut α-quartz exhibits broad OR and EOS responses extending up to approximately 8 THz.
• The THz responses were found to be independent of the crystal thickness.
• These findings suggest a significant surface contribution to the second-order nonlinear susceptibility of quartz at THz frequencies.

Conclusions:

• Crystalline quartz is a reliable medium for THz electro-optic sampling and high-field THz detection.
• The thickness independence of the THz response highlights the importance of surface nonlinearities.
• Quartz can be effectively utilized as a substrate for THz emission applications.