Abstract
Microwave phononics is a promising platform for sensing, computing, and quantum information science; thus, sensitive and high-throughput characterization tools are needed not only for device verification and optimization but also for revealing transient and nonlinear dynamics. Existing interferometric optical vibrometers for 2D mapping are challenged by operating point stabilization, surface reflectivity contrast, and long acquisition time. Here, we use spectral interferometry, which is insensitive to these factors and utilizes a continuous raster scanning scheme for vibration mapping with high throughput. We intensity-modulate our broadband light source with an electro-optic modulator to resolve vibrations at microwave frequencies. Our system requires no fast photodetector or digitizer operating in the microwave frequency range. We image the 1 GHz vibration field of a 300 × 150 µm2 area of an entire surface acoustic wave device in 10 min with simultaneous surface profilometry. Our system has a vibration sensitivity of 120 fm/sqrt(Hz) and a linear throughput of 0.77 mm/s on the chip surface. The technique offers capabilities for characterizing a wide range of acoustic wave and micromechanical devices to better understand their behavior and performance.
| Original language | English |
|---|---|
| Pages (from-to) | 935-944 |
| Number of pages | 10 |
| Journal | Optica |
| Volume | 12 |
| Issue number | 7 |
| DOIs | |
| State | Published - Jul 20 2025 |
Funding
Defense Advanced Research Projects Agency (HR00112320031); Office of Science (CNMS2022-B-01473, CNMS2024-B-02643). This work is partially supported by the Defense Advanced Research Projects Agency (DARPA) OPTIM program. Device fabrication was conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility. Joseph G. Thomas gratefully acknowledges the support of the Bradley Fellowship from the Bradley Department of Electrical and Computer Engineering at Virginia Tech. The views and conclusions contained in this document are those of the authors and do not necessarily reflect the position or the policy of the government. No official endorsement should be inferred. Approved for public release; distribution is unlimited.