Spin-Wave Phase Inverter upon a Single Nanodefect

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Local modification of magnetic properties in nanoelements is crucial for developing advanced magnonic devices that utilize spin waves for information processing.
• A significant challenge lies in creating simple, miniaturized phase-controlling elements with wide-ranging tunability.

Purpose of the Study:

• To realize a miniature, tunable spin-wave phase shifter.
• To investigate the mechanism of phase shifting in magnonic waveguides.
• To demonstrate the potential for on-chip integration in nanomagnonic circuits.

Main Methods:

• Fabrication of a single nanogroove in a Co-Fe magnonic waveguide using focused ion beam milling.
• Experimental tuning of spin-wave phase by varying groove depth and in-plane bias magnetic field.
• Analysis of the microscopic mechanism involving geometrical defects and reduced spin-wave group velocity.

Main Results:

• Successful realization of a spin-wave phase shifter based on a nanogroove.
• Continuous tuning of spin-wave phase and experimental observation of complete phase inversion.
• Identification of reduced magnetization and group velocity under the nanogroove as the key mechanisms.

Conclusions:

• The nanogroove-based phase shifter offers a simple and tunable solution for controlling spin waves.
• The device is readily integrable into existing magnonic circuits and spin-wave logic gates.
• Findings are vital for advancing nanomagnonic circuit design and spin-wave nano-optics.