Related Experiment Video
Updated: Jan 9, 2026
09:33
Demonstration of Equal-Intensity Beam Generation by Dielectric Metasurfaces
Published on: June 7, 2019
6.6K
Multioctave Terahertz Frequency Synthesis via Simultaneous Excitations of Intrinsic and Extrinsic Nonlinearities in
Chen Wang1, Yong Tan1, Yongzheng Wen1
1State Key Laboratory of New Ceramic Materials, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China.
ACS Nano
|December 8, 2025
Summary
Metasurfaces enable efficient terahertz (THz) frequency synthesis, generating 10 discrete THz frequencies across 3.7 octaves. This breakthrough addresses the need for compact, broadband THz sources for advanced communication and radar systems.
Area of Science:
- Photonics and Metamaterials
- Nonlinear Optics
- Terahertz Technology
Background:
- Terahertz (THz) technology advancements are limited by the lack of efficient, compact, and broadband THz sources.
- Frequency synthesis using nonlinear conversion is a promising approach, but requires materials with strong nonlinear responses at THz frequencies.
Purpose of the Study:
- To demonstrate THz frequency synthesis in metasurfaces.
- To generate multiple discrete THz frequency lines with multioctave broadband coverage.
Main Methods:
- Utilizing metasurfaces to simultaneously excite intrinsic third-order and extrinsic second-order nonlinearities.
- Leveraging magnetoelectric coupling induced by metasurface resonance.
- Employing five distinct nonlinear processes: second- and third-harmonic generation, sum- and difference-frequency generation, and four-wave mixing.
Main Results:
- Generation of 10 discrete THz frequencies from 0.3 to 3.9 THz (13-fold spectral range, 3.7 octaves).
- Successful frequency synthesis using only two input frequencies.
- Demonstration of simultaneous dual nonlinear interactions within the metasurface.
Conclusions:
- Metasurfaces offer a scalable and integrable solution for ultrabroadband, frequency-agile THz sources.
- This approach overcomes limitations of existing nonlinear materials for THz generation.
- Paves the way for advanced THz nonlinear devices and applications in communication and radar.
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