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Ultrafast Acoustic Modulation of Second-Harmonic Generation in Monolayer Transition-Metal Dichalcogenides
Takumi Yamamoto1, Hidetoshi Kanzawa1, Yuta Takahashi1
1Department of Physics, Faculty of Science and Technology, Keio University, Yokohama, 223-8522, Japan.
Nano Letters
|March 9, 2026
Summary
We demonstrate ultrafast acoustic modulation of optical nonlinearities in 2D materials using surface acoustic waves (SAWs). This breakthrough enables high-speed control of light-matter interactions for future nanophotonic devices.
Area of Science:
- Nanophotonics
- Materials Science
- Optoelectronics
Background:
- High-speed modulation of optical nonlinearities is crucial for nanoscale optoelectronics.
- Strain engineering modifies material properties but static methods limit device performance.
Purpose of the Study:
- To demonstrate ultrafast acoustic modulation of second-harmonic (SH) generation in 2D materials.
- To establish a dynamic strain engineering platform for nanophotonic devices.
Main Methods:
- Utilized surface acoustic waves (SAWs) for dynamic strain induction.
- Employed phase-synchronized SH measurements and stroboscopic surface displacement detection.
- Performed theoretical modeling to determine photoelastic coefficients.
Main Results:
- Achieved direct visualization of dynamic SH modulation at 226 MHz.
- Quantitatively extracted SAW-induced dynamic strain.
- Established a direct link between acoustic fields and optical nonlinearities.
Conclusions:
- Ultrafast acoustic modulation offers a robust platform for dynamic strain engineering.
- This approach overcomes limitations of static strain methods for nanophotonic devices.
- Enables high-speed control of nonlinear optical processes in 2D materials.
Keywords:
nonlinear opticssecond-harmonic generationsurface acoustic wavestransition metal dichalcogenidestwo-dimensional materialsMore Related Videos
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