Gyrator Based on Magneto-elastic Coupling at a Ferromagnetic/Piezoelectric Interface

Area of Science:

• Acoustics
• Condensed Matter Physics
• Materials Science

Background:

• Gyrators are essential non-reciprocal devices, typically realized electromagnetically.
• Exploration of gyrators based on alternative physical interactions remains limited.
• Magneto-elastic coupling offers a potential pathway for novel device functionalities.

Purpose of the Study:

• To demonstrate a functional gyrator utilizing magneto-elastic coupling and surface acoustic waves (SAW).
• To investigate non-reciprocal signal transmission in a magneto-elastic device.
• To explore the potential of such devices as building blocks for phonon-based information processing.

Main Methods:

• Fabrication of a device on a piezoelectric substrate with interdigital transducers (IDTs) and nickel/gold lines.
• Excitation of Ni magnetization precession via oscillating currents in Au lines, generating SAW through magneto-elastic coupling.
• Detection of emitted SAW by IDTs and detection of SAW-induced magnetization precession by Au lines.
• Exploitation of broken time-reversal symmetry in the ferromagnetic system for non-reciprocity.

Main Results:

• Successful demonstration of a magneto-elastic device functioning as a gyrator.
• Observation of non-reciprocal signal transmission mediated by SAW and magneto-elastic effects.
• Confirmation of signal conversion between acoustic and magnetic domains.

Conclusions:

• Magneto-elastic coupling provides a viable mechanism for realizing non-reciprocal devices like gyrators.
• The developed device serves as a promising component for future phonon-based information processing systems.
• This work expands the scope of gyrator implementations beyond electromagnetic approaches.