Counterpropagating frequency mixing with terahertz waves in diamond

Area of Science:

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

Background:

• Kerr nonlinearity is a fundamental mechanism for frequency conversion across various spectral regions.
• Efficient manipulation of terahertz (THz) radiation is crucial for advancements in spectroscopy, imaging, and communications.

Purpose of the Study:

• To investigate the feasibility of THz wave frequency conversion using optical wave mixing in diamond.
• To explore sum- and difference-frequency generation processes involving THz waves and optical fields.
• To optimize the THz frequency conversion process by examining different geometries.

Main Methods:

• Utilizing diamond as the nonlinear medium for wave mixing.
• Employing an optical field and a THz wave as input.
• Analyzing sum-frequency generation (SFG) and difference-frequency generation (DFG) of the THz radiation.

Main Results:

• Demonstrated successful frequency conversion of THz radiation through wave mixing in diamond.
• Observed both sum- and difference-frequency generation.
• Identified that difference-frequency generation is phase-matched and most efficient in a counterpropagating configuration.

Conclusions:

• Wave mixing of optical fields and THz waves in diamond enables efficient THz frequency conversion.
• The counterpropagating geometry offers optimal phase matching and efficiency for THz difference-frequency generation.
• This work opens new avenues for THz wave manipulation and applications.