A New Approach to Monitoring and Controlling Acoustic Resonators

Silicon carbide, a widely used commercial semiconductor, could hold the key to monitoring and controlling the stability and quality of acoustic resonators, according to researchers from Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) and the OxideMEMS Lab at Purdue University. Acoustic resonators are crucial components of devices like smartphones, Wi-Fi systems, and GPS systems, but their material quality can degrade over time. Currently, there is no simple way to analyze this degradation.

The research team has developed a system that utilizes atomic vacancies in silicon carbide to measure and monitor acoustic resonators’ stability and quality. These vacancies, called quantum reporters, can also have applications in acoustically-controlled quantum information processing, offering a new method to manipulate quantum states in this commonly-used material.

Traditionally, super powerful and expensive x-rays were used to examine the inner workings of acoustic resonators non-destructively. However, these methods are not practical for routine measurements and characterization in manufacturing processes. The use of silicon carbide with embedded quantum reporters provides a more accessible and cost-effective solution.

By shining a laser through the material, researchers can observe changes in the spin state of the defects caused by mechanical strain from acoustic waves. This enables them to map out the acoustic waves inside the resonator without damaging the device. This mapping can help identify areas where the system may be degrading or not operating at its best.

Furthermore, the same defects in silicon carbide can act as qubits in a quantum system, allowing for control of spin by mechanically deforming the material with acoustic waves. This provides an alternative method for controlling the coherence of spins, which is essential in many quantum technologies.

The research, published in Nature Electronics, opens up new possibilities for monitoring and improving the performance of acoustic resonators in various devices. It also highlights the potential of using acoustic waves to control quantum states in materials, expanding our ability to manipulate quantum information.


1. What are acoustic resonators?

Acoustic resonators are components used in electronic devices to filter out noise and improve signal quality. They are commonly found in smartphones, Wi-Fi systems, and GPS systems.

2. How do researchers monitor acoustic resonators using silicon carbide?

Researchers utilize atomic vacancies in silicon carbide, known as quantum reporters, to measure the stability and quality of acoustic resonators. These quantum reporters can interact with sound waves through material strain, allowing researchers to observe changes in the spin state when acoustic waves pass through the material.

3. What are the potential applications of this research?

This research provides a non-destructive method for monitoring the performance of acoustic resonators, which can help identify degradation and optimize device design and fabrication. Additionally, the defects in silicon carbide can be utilized as qubits in quantum systems, offering a new way to control quantum states using acoustic waves. This has potential applications in quantum memories and quantum networking.